Honey

Honey was the most important sweetener in Europe until the 16th century, when cane sugar and its more neutral sweetness became more widely available. Germany and the Slavic countries were leading producers in the meantime, and honey wine or mead (from the Sanskrit word for “honey”) was a great favorite in both central Europe and Scandinavia. Honey is now valued as an alternative to sugar, a premade syrup with many distinctive flavors to offer.

The Honeybee While the New World certainly knew and enjoyed honey before the arrival of European explorers, North America did not. The bees native to the New World, species of the genera Melipona and Trigona, are exclusively tropical. They also differ from the European honeybees in being stingless and in collecting fluids not just from flowers, but also from fruits, resins, and even carrion and excrement — sources that make for unhealthful honeys as well as rich and strange flavors. European colonization brought a fundamental change to North America by introducing, around 1625, the bee that produces practically all the honey in the world today, Apis mellifera.

Bees are social insects that have evolved along with nectar-producing flowering plants. The two organisms help each other out: plants provide the insects with food, and insects carry cross-fertilizing pollen from one flower to another. Honey is the form in which flower nectar is stored in the hive. It appears from the fossil record that bees have been around for some 50 million years, their social organization for half that time. Apis, the principal honey-producing genus, originated in India. Apis mellifera, the honey bee proper, evolved in subtropical Africa and now inhabits the whole of the Northern Hemisphere up to the Arctic Circle.

How Bees Make Honey

Nectar The principal raw material of honey is the nectar collected from flowers, which produce it in order to attract pollinating insects and birds. Secondary sources include nectaries elsewhere on the plant and honeydew, the secretions of a particular group of bugs. The chemical composition of nectar varies widely, but its major ingredient by far is sugars. Some nectars are mostly sucrose, some are evenly divided among sucrose, glucose, and fructose, and some (sage and tupelo) are mostly fructose. A few nectars are harmless to bees but poisonous to humans, and so generate toxic honeys. Honey from the Pontic region of eastern Turkey was notorious in ancient Greece and Rome; a local species of rhododendron carries “grayanotoxins,” which interfere with both lung and heart action.

The most important sources of nectar are the flowers of plants in the bean family, especially clover, and in the lettuce family, a large group that includes the sunflower, dandelion, and thistles. Though most honey is made from a mixture of nectars from different flowers, some 300 different “monofloral” honeys are produced in the world, with citrus, chestnut, buckwheat, and lavender honeys especially valued for their distinctive tastes. Some honeys, chestnut and buckwheat in particular, are much darker than others, thanks in part to the higher protein content in their nectars, which reacts with the sugars to produce dark pigments as well as a toasted aroma.

Gathering Nectar The bee gathers nectar from a flower by inserting its long proboscis down into the nectary. In the process, its hairy body picks up pollen from the flower’s anthers. The nectar passes through the bee’s esophagus into the honey sac, a storage tank that holds the nectar until the bee returns to the hive. Certain glands secrete enzymes into the sac, and these work to break down starch into smaller chains of sugars and sucrose into its constituent glucose and fructose molecules.

A few remarkable figures are worth quoting. A strong hive contains one mature queen, a few hundred male drones, and some 20,000 female workers. For every pound of honey taken to market, eight pounds are used by the hive in its everyday activities. The total flight path required for a bee to gather enough nectar for this pound of surplus honey has been estimated at three orbits around the earth. The average bee forages within one mile of the hive, makes up to 25 round trips each day, and carries a load of around 0.002 of an ounce, or 0.06 grams — approximately half its weight. With its light chassis, a bee would get about 7 million miles to a gallon (3 million km per liter) of honey. In a lifetime of gathering, a bee contributes only a small fraction of an ounce of honey to the hive.

Transforming Nectar into Honey In the hive, the bees concentrate the nectar to the point that it will resist bacteria and molds and so keep until it is needed. “House bees” pump the nectar in and out of themselves for 15 or 20 minutes, repeatedly forming a thin droplet under their proboscises from which water can evaporate, until the water content of the nectar has dropped to 50 or 40%. The bees then deposit the concentrated nectar in a thin film on the honeycomb, which is a waxy network of hexagonal cylinders about 0.20 inch/5 mm across, built up from the secretions of the wax glands of young workers. Here, with workers keeping the hive air in continuous motion by fanning their wings, the nectar loses more moisture, until it’s less than 20% water. This process, known as “ripening,” takes about three weeks. The bees then fill the honeycomb cells to capacity with fully ripe honey and cap them with a layer of wax.

The ripening of honey involves both evaporation and the continuing work of bee enzymes. One important enzyme converts the sucrose almost entirely to glucose and fructose, because a mixture of single-unit sugars is more soluble in water than the equivalent amount of its parent sucrose, and so can be more highly concentrated without crystallizing. Another enzyme oxidizes some glucose to form gluconic acid and peroxides. Gluconic acid lowers the honey’s pH to about 3.9 and makes it less hospitable to microbes, and the peroxides also act as an antiseptic. In addition to these and other enzyme activities, the various components of ripening honey react with each other and cause gradual changes in color and flavor. Hundreds of different substances have been identified in honey, including more than 20 different sugars, savory amino acids, and a variety of antioxidant phenolic compounds and enzymes.

Honeycomb, and the anatomy of the worker bee. Worker bees hold freshly gathered nectar in the honey sac, together with enzymes from various glands, until they return to the hive.

Processing Honey Some honey is sold in its beeswax honeycomb, but producers extract most of their honey from the comb and then treat it to extend its shelf life. They remove the honeycomb from the hive and spin it in a centrifuge to separate liquid honey from solid wax. They then generally heat the honey to around 155ºF/68ºC to destroy sugar-fermenting yeasts, strain it to remove pieces of wax and debris, sometimes blend it with other honeys, and finally filter it under pressure to remove pollen grains and very small air bubbles that would cloud the liquid. The honey may be packaged as a liquid at this stage, or else crystallized to form a spreadable paste, or “cream,” that doesn’t run and drip the way liquid honey does. Though it seems solid, 85% of cream honey remains in its liquid form, dispersed around the 15% that has solidified into tiny crystals of glucose.

Because all sugars become increasingly soluble as the temperature rises, cream honey softens and begins to melt into liquid honey when it’s warmed above about 80ºF/26ºC. By the same token, liquid honey that has granulated during storage can be reliquefied with gentle heat.

Storing Honey Honey is one of our more stable foods, but unlike table sugar it can spoil. This is because it contains some moisture and absorbs more from the air whenever the relative humidity exceeds 60%. Sugar-tolerant yeasts can grow on the honey and produce off-flavors. It’s therefore best to store honey in a moisture-tight container.

Thanks to its high concentration of sugars and the presence of some amino acids and proteins, honey is prone to undesirable, flavor-flattening browning reactions, not just when heated, but also when stored for a long time at room temperature. If you use honey infrequently, it’s best to keep it at temperatures below 50ºF/15ºC. Liquid honey will slowly granulate in the refrigerator, and cream honey will get somewhat coarser.

Honey Flavor The most delightful quality of honeys is their flavors, which make them into natural sauce-like condiments. All honeys share a sweet taste base that is slightly tart and savory as well, and a complex aroma that has several different elements: caramel, vanilla, fruity (esters), floral (aldehydes), buttery (diacetyl), sweet-spicy (sotolon, p. 418). Then honeys made from single nectars add their own distinctive notes. Buckwheat honey is malty (methylbutanal); chestnut honey carries the distinct note of corn tortillas (aminoacetophenone, with both floral and animal elements); citrus and lavender honeys are citrusy and herbal but share a grapy note (methyl anthranilate); linden honey includes a mixture of mint, thyme, oregano, and tarragon aromatics.

Honey in Cooking Unlike sugar, which is often a hidden ingredient in processed foods, honey is a very visible sweetener; most of it is added to foods by individual consumers. With its syrup-like viscosity, glossiness, and range of brown shades, it makes an attractive topping for pastries and other foods. It is the characteristic sweetener in such pastries as baklava and lebkuchen, such confections as nougat and torrone, halvah and pasteli, and in such liqueurs as Benedictine, Drambuie, and Irish Mist. Although honey wine, or mead, has all but disappeared, honey beer is popular in Africa. Americans use honey in many baked goods for a variety of reasons. It can be substituted for sugar — 1 measure of honey is considered the sweetening equivalent of 1.25–1.5 measures of sugar, although the amount of added liquid must be decreased because honey does contain some water. Because it is more hygroscopic, or water attracting, than table sugar, honey will keep breads and cakes moister than sugar will, losing water to the air more slowly, and even absorbing it on humid days. Thanks to its antioxidant phenolic compounds, it slows the development of stale flavors in baked goods and warmed-over flavors in meats. Bakers can use its acidity to react with baking soda and leaven quickbreads. And its reactive reducing sugars accelerate desirable browning reactions and the development of flavor and color in the crusts of baked goods, in marinades and glazes, and other preparations.

Honey and Health; Infant Botulism Though honey has not been refined the way table sugar is and is chemically complex, it is no wonder food. Its vitamin content is negligible; bees get most of theirs from pollen. Its antibacterial properties, which led early physicians to use it to dress wounds, are due largely to hydrogen peroxide, one of the products of glucose-oxidizing enzyme and a substance well known and long employed in medicine. And honey should not be fed to children less than a year old. It often carries the seed-like dormant spores of the botulism bacterium (Clostridium botulinum), which are able to germinate in immature digestive systems. Infant botulism can cause difficulty in breathing and paralysis.

Tree Syrups and Sugars: Maple, Birch, Palm

When bees make honey, they perform two basic tasks: they remove a very dilute solution of sugar from plants, and then evaporate off most of the water. What the bees evolved to do instinctively and with their own muscles and enzymes, humans have learned to do with the help of tools and fire. We make syrups and sugars by extracting dilute juices from plants, and then boiling off most or all of the water. Of the man-made sweets, tree syrups and sugars are most like honey in that they retain nearly all the original contents of the sap, and are not refined to the extent that cane and beet sugars are.

Maple Syrup and Sugar Long before Europeans introduced the honeybee, the natives of North America had developed their own delicious concentrated sweets. Several Indian tribes, notably the Algonquins, Iroquois, and Ojibways, had well-established myths about and terminologies for maple sugaring by the time that European explorers encountered them. Thanks to a remarkable document, we have some idea of how ingenious they were at extracting and concentrating the tree sap (see box below). All they needed was a tomahawk to cut into the tree, a wood chip to keep the wound open, sheets of elm bark for containers, and cold nights to freeze the water into pure ice crystals that could then be removed from the ever more concentrated sap.

Maple sugar was an important part of the native Americans’ diet, worked into bear fat, or mixed with corn meal to make a light, compact provision for journeys. For the colonists, maple sugar was cheaper and more available than the heavily taxed cane sugar from the West Indies. Even after the Revolution, many Americans found a moral reason for preferring maple sugar to cane; cane sugar was produced largely with slave labor. Toward the end of the nineteenth century, cane and beet sugar became so cheap that the demand for maple sugar declined steeply. Today the production of maple syrup is a cottage industry concentrated in the eastern Canadian provinces, especially Quebec, and in the American Northeast.

The Sap Run The maple family originated in China or Japan and numbers some 100 species throughout the Northern Hemisphere. Of the four North American species good for sugaring, the hard or rock maple, Acer saccharum, produces sap of greater quality and in greater quantity than the others, and accounts for most of the syrup produced today. In the spring, sap is collected from the first major thaw until the leaf buds burst, at which point the tree fluids begin to carry substances that give the syrup a harsh flavor. The sap run is improved by four conditions: a severe winter that freezes the roots, snow cover that keeps the roots cold in the spring, extreme variations in temperatures from day to night, and good exposure to the sun. The northeastern states and eastern Canadian provinces meet these needs most consistently.

Sap does run in other trees in early spring, and some of them — birch, hickory, and elm, for example — have been tapped for sugar. But maples produce more and sweeter sap than any other tree, thanks to an intricate physical mechanism by which the tree forces sugars from the previous growing season out of storage in the trunk and into the outer, actively growing zone, the cambium.

Syrup Production From colonial times to the 20th century, sugar producers collected the sap by punching a small hole in the maple tree, inserting a wooden or metal spout into the cambium, and hanging a bucket into which the sap dripped. This picturesque collection method has mostly given way to systems of plastic taps and tubing, which carry the sap from many trees to a central holding tank. Over a six-week season, the taps remove around 10% of a tree’s sugar stores, in an average of 5 to 15 gallons/20–60 liters per tree (some give as much as 80 gallons). It takes around 40 parts of sap to make 1 part syrup. The sap contains around 3% sucrose at the beginning of the season, half that at the end; so late-season sap must be boiled longer and is therefore darker and stronger-flavored. Today, many producers use energy-efficient reverse osmosis devices to remove about 75% of the sap water without heat, then boil the concentrated sap to develop its flavor and obtain the desired sugar concentration. They aim for a temperature around 7ºF/4ºC above the boiling point of water, the equivalent of a syrup that’s around 65% sugars.

The Flavors of Maple Syrups The final composition of maple syrup is approximately 62% sucrose, 34% water, 3% glucose and fructose, and 0.5% malic and other acids, and traces of amino acids. The characteristic flavor of the syrup includes sweetness from the sugars, a slight tartness from the acids, and a range of aroma notes, including vanilla from vanillin (a common wood by-product) and various products of sugar caramelization and browning reactions between the sugars and amino acids. The longer and hotter the syrup is boiled, the darker the color and the heavier the taste. Maple syrups are graded according to color, flavor, and sugar content, with grade A assigned to the lighter, more delicately flavored, sometimes less concentrated syrups that are poured directly onto foods. Grades B and C are stronger in caramel flavor and are more often used for cooking, for example in baked goods and meat glazes. Because true maple syrup is expensive, many supermarket syrups contain little or none, and are artificially flavored.

Maple Sugar Maple sugar is made by concentrating the syrup’s sucrose to the point that it will crystallize when the syrup cools. This point is marked by a boiling temperature of 25–40ºF/14–25ºC above the boiling point of water, or 237–250ºF/114–125ºC at sea level. Left to itself, the syrup will form coarse crystals thinly coated with the remainder of the brown, flavorful syrup. Maple cream, a malleable mixture of very fine crystals in a small amount of dispersed syrup, is made by cooling the syrup very rapidly to about 70ºF/21ºC by immersing the pan in baths of iced water, and then beating it continuously until it becomes very stiff. This mass is then gently rewarmed until it becomes smooth and semisoft.

Birch Syrup The inhabitants of far northern parts of the globe, including Alaska and Scandinavia, have long made a sweet syrup from the sap of birch trees, various species of Betula that are the dominant forest trees in northern latitudes. Birch sap runs for two to three weeks in early spring. It is much more dilute than maple sap, around 1% sugars, mainly an even mixture of glucose and fructose. It takes around 100 parts of sap to make 1 of syrup, both because there’s less sugar to begin with, and because a mixture of glucose and fructose is thinner than the equivalent amount of sucrose; producers therefore aim for a final sugar concentration of 70–75%. Thanks to the different sugars and their reactions, the syrup is reddish brown and has a more caramel-like flavor than maple syrup; the level of vanillin is lower, too.

Palm Syrup and Sugar; Agave Syrup Among sugar-giving trees, certain tropical palms are by far the most generous. The Asian sugar palm (Borassus flabellifer) can be tapped for up to half the year, and yields 15–25 quarts/liters per day of a sap that may be 12% sucrose! Individual trees can give 10–80 pounds of raw sugar every year. Coconut, date, sago, and oil palms are less productive, but still far more so than maples and birches. The sap is collected either from the flowering stalks at the top of the tree, or from taps in the trunk, and then is boiled down either to a syrup called palm honey, or to a crystallized mass, which in India is known as gur (Hindi) or jaggery(English, via Portuguese from the Sanskrit sharkara). These same words are also used for unrefined cane sugars. Unrefined palm sugar has a distinctive, winey aroma that contributes to the flavor of Indian, Thai, Burmese, and other South Asian and African cuisines. Some palm sugar is refined to make more neutral white sugar.

Agave syrup is produced from the sap of various species of agave, desert plants native to the New World that are related to the cactus family. The sugars in agave syrup are about 70% fructose and 20% glucose, so this syrup tastes sweeter than most.

Table Sugar: Cane and Beet sugars and Syrups

The processing of cane and beet sugar is much more complicated than the production of honey and maple and palm sugars, and for one basic reason. Bees and tree tappers begin with an isolated plant fluid that contains little else besides water and sugar. But the raw material for table sugar is the crushed whole stem of the cane, or the whole root of the beet. Cane and beet juices include many substances — proteins, complex carbohydrates, tannins, pigments — that not only interfere with the sweet taste themselves, but decompose into even less palatable chemicals at the high temperatures necessary for the concentration process. Cane and beet sugar must therefore be separated from these impurities.

Preindustrial Sugar Refining From the late Middle Ages until the 19th century, when machinery changed nearly every sort of manufacturing, the treatment of sugar followed the same basic procedure. There were four separate stages:

• clarifying the cane juice
• boiling it down into a thick syrup to concentrate and crystallize the sucrose
• draining the impurity-laden syrup from the solid crystals
• washing the remaining syrup from the crystals

The cane stalks were first crushed and pressed, and the resulting juice was cleared of many organic impurities by heating it with lime and a substance such as egg white or animal blood, which would coagulate and trap the coarse impurities in a scum that could be skimmed off. The remaining liquid was then boiled down in a series of shallow pans until it had lost nearly all of its water, and poured into cone-shaped clay molds a foot or two long with a capacity of 5 to 30 lb/2–14 kg. There it was cooled, stirred, and allowed to crystallize into “raw sugar,” a dense mass of sucrose crystals coated with a thin layer of syrup containing other sugars, minerals, and various dissolved impurities. The clay cones were left to stand inverted for a few days, during which time the syrup film, or molasses, would run off through a small hole in the tip. In the final phase, a fine wet clay was packed over the wide end of the cone, and its moisture was allowed to percolate through the solid block of sugar crystals for eight to ten days. This washing, which could be repeated several times, would remove most of the remaining molasses, though the resulting sugar was generally yellowish.

Modern Sugar Refining Today, sugar is produced by somewhat different means. Because most sugarcane has been grown in colonies or developing countries, and sugar refining requires expensive machinery, cane sugar production came to be divided into two stages: the crystallization of raw, unrefined sugar in factories near the plantations; and refining into white sugar in industrial countries that are the major consumers. Sugar beets, on the other hand, are a temperate crop, grown mainly in Europe and North America, so they are processed all the way to refined sugar in a single factory. Harvested sugarcane is very perishable and must be processed immediately; sugar beets may be stored for weeks to months before they are processed into sugar.

Sugar production requires two basic kinds of work: crushing the cane to collect the juice, and then boiling off the juice’s water. The crushing is hard physical labor, and the boiling requires large amounts of heat. In the Caribbean, these needs were filled by slave labor and deforestation. Three 19th-century innovations helped make sugar a less costly pleasure: the application of steam power to the crushing; the vacuum pan, which boils the syrup at reduced pressure and so at a lower, gentler temperature; and the multiple evaporator, which recycles the heat of one evaporation stage to heat the next.

The initial clarification of cane and beet juice is now accomplished without eggs or blood; heat and lime are generally used to coagulate and remove proteins and other impurities. Rather than waiting for gravity to draw off molasses, refiners use centrifuges, which spin the raw sugar as a salad spinner spins greens, forcing the liquid off the crystals in minutes rather than weeks. The sucrose is whitened by the technique of decolorization, in which granular carbon — a material like activated charcoal that can absorb undesirable molecules on its large surface area — is added to the centrifuged, redissolved sugar. After it absorbs the last remaining impurities, the charcoal is filtered out. The final crystallization process is carefully controlled to give individual sugar crystals of uniform size. Our table sugar is an astonishingly pure 99.85% sucrose.

Impurities in White Sugar It turns out that the tiny fraction of impurities in table sugar can make a noticeable difference in its color and flavor. Make a concentrated syrup from just water and sugar and it will have a yellow, sometimes hazy cast, thanks to large carbohydrate and pigment molecules that either get trapped between sucrose molecules as they crystallize, or remain stuck to the crystal surface. Beet sugar in particular sometimes carries earthy, rancid off-odors. Where sugarcane grows above the ground and is so perishable that it is processed immediately after harvest, the beet grows underground and may be stored for weeks or months between harvest and processing, during which time it can be tainted by soil bacteria and molds that remain on its surface. In addition, beet sugar sometimes carries traces of defensive chemicals called saponins, which resemble soaps. These are known to cause the development of a scum in syrups, and may also be responsible for the poor baking performance sometimes attributed to beet sugar. (This reputation may be an undeserved legacy of the early 20th century, when refining techniques weren’t as effective and the quality of beet sugar often didn’t measure up to that of cane sugar.)

Kinds of White Sugar White sugar comes in a number of different forms, which differ mainly in the size of the crystals. They go by many different names. Ordinary table sugar, used for general cooking and dissolving in drinks, is midsized. Coarser crystals are mainly used for decorating baked goods and confections, and for that reason are specially treated to produce a sparkling, crystal-clear appearance. They are made from exceptionally pure batches of sucrose, with the least possible residue of the impurities that give ordinary sugar solutions a yellowish look. They’re even washed with alcohol to remove sucrose dust on their surfaces. When a cook wants to make the whitest possible fondant, or the clearest possible syrup, it’s best to use these coarse or “sanding” sugars.

At the finer end of the scale, there are a number of sugars with smaller particles than table sugar. Extra-fine, baker’s special, and English caster sugars all offer more crystalline surfaces that can introduce air into fat during the creaming stage of making cakes (p. 556). “Powdered” sugars have been ground into even smaller particles, some small enough that they offer no roughness to the tongue, and can be made directly into very smooth icings, frostings, and fillings. Powdered sugars contain around 3% starch by weight to absorb moisture and prevent caking, and therefore have a slightly floury taste and feeling on the tongue.

OPPOSITE: Making cane sugar. The initial processing of sugar cane into raw sugar is carried out in tropical and sub-tropical cane-growing countries; most of the subsequent refining of raw sugar into white sugar in consuming countries. Beet sugar is made in essentially the same way, except that most sugar beets are grown in temperate industrialized countries and processed there, and beet molasses and syrups are not palatable.

Brown Sugars Brown sugars are sucrose crystals that are coated with a layer of dark syrup from one or another stage of sugar refining, and therefore have a more complex flavor than pure sucrose. There are several basic kinds of brown sugars.

Factory Brown Sugars “Factory” brown sugars were originally produced during the initial processing of the cane juice into unrefined sugar. These include demerara, turbinado, and muscovado sugars. Demerara (named after a region in Guyana) came from the first crystallization stage of light cane juice, and took the form of sticky, large, yellow-gold crystals. Turbinado was raw sugar partly washed of its molasses coat during the centrifugation, also yellow-gold and large but not as sticky as demerara. Muscovado was the product of the final crystallization from the dark mother liquor (p. 675); it was brown, small-grained, sticky, and strong-flavored.

Refinery Brown Sugars Today, these evocative names of factory sugars are often applied to a different product, brown sugars produced at the refinery using raw sugar as the starting material, not the cane juice. All ordinary brown sugar is also made in this way. There are two ways to make refinery brown sugars: redissolving the raw sugar in a syrup of some kind and then recrystallizing it, so that it retains some of the syrup on its crystal surfaces; or refining the raw sugar all the way to pure white sugar, and then coating or “painting” its surfaces with a thin film of syrup or molasses.

The basic difference between factory and refinery brown sugars is that true factory sugars retain more of the flavor of the original cane juice, including green, fresh, and vegetable-ocean aromas (from hexanol, acetaldehyde, and dimethyl sulfide). Both kinds have an important vinegar aroma (from acetic acid), as well as caramel and buttery notes (the buttery one from diacetyl, indeed found in butter), and salty and bitter tastes (from minerals). Refinery brown sugars also develop what’s described as a licorice aroma from the long, slow heating of the syrups.

Whole Sugars It’s still possible to taste what might be called whole sugar, crystalline sugar still enveloped in the cooked cane juice from which it formed. This is the sugar sold in Indian groceries as jaggery or gur, and in Latin American shops as piloncillo, papelon, or panela. The flavor is highly variable, and ranges from mild caramel to strong molasses.

Using Brown Sugars Brown sugar is soft and clingy because its molasses film — whose glucose and fructose are more hygroscopic than sucrose — contains a significant amount of water. Of course, if brown sugar is left exposed to dry air, it will lose its moisture through evaporation and become hard and lumpy. It can be kept moist by storing it in an airtight container, and resoftened by closing it up with a damp towel or piece of apple from which it can absorb moisture. Because brown sugar tends to trap air pockets between groups of adhering crystals, it should be packed down before its volume is measured.

Molasses and Cane Syrups

Molasses Molasses, which is called treacle in the United Kingdom, is generally defined as the syrup left over in cane sugar processing after the readily crystallizable sucrose has been removed from the boiled juice. (There is such a thing as beet molasses, but it has a strong, unpleasant odor, and so is used to feed animals and industrial fermentation microbes.) In order to extract as much sucrose as possible from cane juices, crystallization is performed in several different steps, each of which results in a different grade of molasses. “First” molasses is the product of centrifuging off the raw sugar crystals, and still contains some sucrose. It is then mixed with some uncrystallized sugar syrup, recrystallized, and recentrifuged. The resulting “second” molasses is even more concentrated in impurities than the first. Repeating this process once more yields “third,” or final, or “blackstrap” molasses (from the Dutch stroop for “syrup”). The brown-black color of final molasses is due to the extreme caramelization of the remaining sugars and to chemical reactions induced by the high temperatures reached during the repeated boilings. These reactions, together with the high concentration of minerals, give final molasses a harsh flavor that makes it generally unfit for direct human consumption, although it’s sometimes sold blended with corn syrup. A small amount is also used in tobacco curing.

Kinds of Molasses First and second molasses have been used in foods for many years, and for a long time were the only form of sugar available to slaves and the poor of the rural South, usually bleached with sulfur dioxide and strongly sulfurous to the taste. Today, most molasses available to consumers are actually blends of molasses and syrups from various stages throughout the sugar-making process. They range from mild to pungent and bitter, from golden brown to brown-black. The darker the molasses, the more its sugars have been transformed by caramelization and browning reactions, and so the less sweet and more bitter it is. Light molasses may be 35% sucrose and 35% invert sugars, and 2% minerals; blackstrap molasses may be 35% sucrose, 20% invert sugars, and 10% minerals.

Molasses in Cooking The flavor of cane molasses is complex, with woody and green notes as well as sweet, caramel, buttery ones. Its complexity has made it a popular background flavor in many foods; popcorn balls, gingerbread, licorice, barbeque sauces, and baked beans are examples. Cane molasses is usually but unpredictably acidic; its pH varies between 5 and neutral 7, so it can sometimes react with baking soda and produce leavening carbon dioxide in baked goods. Thanks to its invert sugars, it helps retain moisture in foods. And a variety of components contribute to a general antioxidant capacity, which helps slow the development of off-flavors.

Cane and Sorghum Syrups Cane syrups may be produced directly from cane juice at sugar factories, or from raw sugar at refineries. They generally contain a combination of sucrose (25–30%) and invert sugars (50%), are golden to medium brown in color, and have a mild flavor with caramel, butterscotch, and leafy aromas. Louisiana cane syrups were traditionally made from whole cane juice, concentrated and clarified. The same basic product, with about half of its sucrose inverted by acid or enzymes, is now sometimes called “high-test molasses.” It has been heated less, and so has a more aromatic, less bitter flavor than true molasses. “Golden syrup” is a refinery syrup made from raw sugar, filtered through charcoal to give it a characteristic light, crystal-clear appearance and delicate flavor. Cane syrups offer more character (though also a more intense sweetness) than corn syrup in such dishes as pecan pie.

Sorghum syrup is made in small quantities in the American South and Midwest from the stalk juice of sweet sorghum, specialized varieties of a cereal plant normally grown for its grain (Sorghum bicolor, p. 482). Sorghum syrup is mainly sucrose, and has a distinctive pungency.

Corn Syrups, Glucose and Fructose Syrups, Malt Syrup

Sugars from Starch We come now to a source of sugar that is relatively new, but today rivals cane and beet sugars in commercial importance. In 1811, a Russian chemist, K. S. Kirchof, found that if he heated potato starch in the presence of sulfuric acid, the starch was transformed into sweet crystals and a viscous syrup. A few years later, he discovered that malted barley had the same effect as the acid (and thereby laid the foundations for a scientific understanding of beer brewing). We now know that starch consists of long chains of glucose molecules, and that both acids and certain plant, animal, and microbial enzymes will break these long chains down into smaller pieces and eventually into individual glucose molecules. The sugars make the syrup sweet, and the remaining fragments of glucose chains give the solution a thick, viscous consistency. In the United States, the acid technique was used to produce syrup from potato starch in the 1840s, and from corn starch beginning in the 1860s.

High-Fructose Corn Syrups The 1960s brought the invention of fructose syrups. These start out as plain corn or potato syrups, but an additional enzyme process converts some of the glucose sugars into fructose, which is much sweeter and therefore gives the syrups a higher sweetening power. The solids in standard high-fructose corn syrup are around 53% glucose and 42% fructose, and provide the same sweetness as the syrup’s equivalent weight in table sugar. Because high-fructose syrups are relatively cheap, soft-drink manufacturers began to replace cane and beet sugars with them in the 1980s, and Americans began to consume more corn syrups than cane and beet sugar. Today they’re a very important sweetener in food manufacturing.

Making Corn Syrups To make corn syrups, manufacturers extract starch granules from the kernels of common dent corn (p. 477), and then treat them with acid and/or with microbial or malt enzymes to develop a sweet syrup that is then clarified, decolorized, and evaporated to the desired concentration. Nowadays, enzymes from the easily cultured molds Aspergillus oryzae (also used in Japan to break rice starch down into fermentable sugars for sake) and A. niger are used almost exclusively. In Europe, potato and wheat starch are the main sources for making what is called “glucose” or “glucose syrup,” which is essentially the same as American corn syrup.

The Properties and Uses of Corn Syrups Among the usual sweeteners available to the cook, corn syrups are alone in providing long carbohydrate molecules that get tangled up with each other and slow down the motion of all molecules in the syrup, thus giving it a thicker consistency than any but the most concentrated sucrose syrups. It’s largely these long tangly molecules that have made corn syrup increasingly important in confectionery and other prepared foods. Because the tangling interferes with molecular motion, it also has the valuable effect of preventing other sugars in candy from crystallizing and producing a grainy texture. All molecules in the syrup are flowing very slowly, and the sucrose crystal faces keep getting covered with chains that can’t become part of the crystal. (The same behavior helps minimize the size of ice crystals in ice cream and fruit ices, thus encouraging a smooth, creamy consistency.) Another consequence of corn syrup’s viscosity is that it imparts a thick, chewy texture to foods. And because it includes glucose, a water-binding sugar that is less sweet than table sugar, corn syrup helps prevent moisture loss and prolongs the storage life of various foods without the cloying sweetness that honey or sucrose syrup imparts. Finally, all corn syrups are somewhat acid, with a pH between 3.5 and 5.5, so in baked goods they can react with baking soda to produce carbon dioxide and thus contribute to leavening.

Corn syrups. Standard corn syrup is a water solution of glucose chains of varying lengths (left). One-and two-unit sugars taste sweet, while taste-free longer chains make the syrup viscous. By controlling the relative populations of different chains, the manufacturer can tailor the syrup’s balance of sweetening and thickening powers. High-fructose corn syrup (right) has been treated with an enzyme to convert a portion of the single glucose molecules (small hexagons) into fructose molecules (small pentagons), which taste sweeter.

Grades of Corn Syrup Corn syrup is an especially versatile ingredient in food manufacturing because its sweetness and viscosity can be varied simply by controlling the thoroughness of the enzymatic digestion of starch into sugars. The most common consumer grade of corn syrup is about 20% water, 14% glucose, 11% maltose, and 55% longer glucose chains. It is only moderately sweet, and fairly viscous. Several others grades are available to manufacturers:

• Maltodextrins are syrups that contain less than 20% glucose plus maltose, and are used mainly to give viscosity and body with little sweetness and moisture absorption.
• High-fructose corn syrups are around 75% fructose plus glucose, and give an overall sweetness around that of table sugar. They and high-glucose syrups help develop color and retain moisture in baked goods.
• High-maltose syrups are valuable in ice creams, and some confections, where lowered freezing points or interference with crystallization are desired but sweetness is not; maltose is less sweet than either table sugar or glucose. In baked goods, maltose feeds yeasts and improves leavening.

Malt Syrup and Extract Malt syrup is made from a combination of germinated cereal grains, preeminently barley, and ordinary cooked grains. It’s among the most ancient and versatile of sweetening agents, and was the predecessor of modern-day high-tech corn syrups. Along with honey, malt syrup was the primary sweetener in China for 2,000 years, until around 1000 CE; it’s still made in both China and Korea. Malt syrup had the advantage that it could be made in households from readily available and easily stored materials, the same whole grains that were grown as staple foods, including wheat, rice, and sorghum. It was therefore a far more affordable sweetener than cane sugar.

There are three stages to making malt syrup. First a portion of whole grain is malted: soaked in water and allowed to germinate partly, then dried again by means of carefully controlled heating (p. 744). The germinating embryo produces enzymes that will digest the grain’s starch into sugars to fuel its growth; barley is preferred in malting because it produces unusually copious and active enzymes. Drying preserves these enzymes, and also develops color and flavor by means of browning reactions. In the second stage, the malted grain is mixed with some water and with unmalted but cooked grains — rice, wheat, barley — and the malt enzymes digest the cooked starch granules to produce a sweet slurry. In the final stage, the slurry is extracted with additional water, and the liquid is boiled down to concentrate it. The result is a concentrated syrup of maltose, glucose, and some longer glucose chains. Malt syrup is therefore much less sweet than a similarly viscous sucrose syrup. In Asia it is used to provide color and gloss in savory dishes — for example, it’s painted onto the skin of Peking duck — as well as in confections.

Malt syrup has a relatively mild malt aroma because the malted barley is a small fraction of the grain mixture. If the malted barley is soaked on its own, without any added cooked grains, then the malt flavor is much stronger. Such a preparation is usually called “malt extract.” It is frequently used in baking to provide maltose and glucose for yeast growth and moisture retention (p. 530). In the United States, malted milk and malt balls are made from a mixture of barley malt and powdered milk.

Sugar Candies
and Confectionery

All sugar candies, whether brittle or creamy or chewy, are essentially mixtures of two ingredients: sugar and water. Cooks manage to create very different textures from the same materials by varying the relative proportions of sugar and water, and the physical arrangement of the sugar molecules. They control the proportions as they cook the sugar syrup, and they control the physical arrangement as they cool it. Depending on how hot the syrup gets, how quickly it cools, and how much it’s stirred, it can solidify into coarse sugar crystals, fine sugar crystals, or a monolithic crystal-free mass. To a large extent, the art of the confectioner depends on the science of crystallization.

Setting the Sugar
Concentration:
Cooking the Syrup

The first factor that influences candy texture is the concentration of sugar in the cooked syrup. Confectioners have found from long experience that certain syrup concentrations are best for making certain kinds of candy. Generally, the more water the syrup contains, the softer the final product will be. So the cook must know how to make and recognize particular syrup concentrations. This turns out to be pretty simple. When we dissolve sugar or salt in water, the boiling point of the solution becomes higher than the boiling point of pure water (see p. 785). This increase in the boiling point depends predictably on the amount of material dissolved: the more dissolved molecules in the water, the higher the boiling point. So the boiling point of a solution is an indicator of the concentration of the dissolved material. The graph in the box below shows, for example, that a sugar syrup that boils at 250ºF/125ºC is about 90% sugar by weight.

Cooking the Syrup Raises the Sugar Concentration As a sugar solution boils, water molecules evaporate from the liquid phase into the air, while the sugar molecules stay behind. The sugar molecules therefore account for a larger and larger proportion of all the molecules in the solution. So as it boils, the syrup gets more and more concentrated: and this in turn causes its boiling point to continue to rise. In order to make a syrup of a given sugar concentration, all the candy maker has to do is heat a mixture of sugar and water until it boils, and then keep it at the boil and watch its temperature. At 235ºF/113ºC, or about 85% sugar, the cook can stop the concentration process and make fudge; at 270ºF/132ºC, or 90%, taffy; at 300ºF/149ºC and above, nearing 100% sugar, brittles and hard candies.

The Cold-Water Test Although it was invented 400 years ago by Sanctorius, the thermometer has been a common household appliance for only a few decades. Beginning in the 16th century and continuing to this day, confectioners have used a more direct means of sampling the syrup’s fitness for different candies: they scoop out a small amount, cool it quickly, and note its behavior. Thin syrups will simply form a thread in the air. Somewhat more concentrated syrups form a ball when dropped into cold water, and the ball will be soft and malleable between the fingers; as the concentration increases, the cooled ball becomes harder. The most concentrated syrups make a cracking sound as they turn into hard, brittle threads. Each of these stages indicates a particular temperature range and suitability for a particular kind of candy (see box below).

The Heating Rate Accelerates During Cooking As we cook a sugar syrup, most of the heat goes into the work of evaporating water molecules from the syrup, and less into actually raising the temperature of the syrup; so the syrup temperature rises only gradually. But as the sugar concentration passes 80%, there’s so little water left that both the temperature of the syrup and its boiling point rise more rapidly. As the concentration approaches 100%, the temperature rises very fast, and can easily overshoot the desired range and brown or scorch the sugar. To avoid this, the cook should reduce the heat toward the end of cooking and keep a careful eye on the syrup temperature.

Setting the Sugar Structure: Cooling and Crystallization

The final texture of a candy is determined by the way in which the sugar molecules in the cooked syrup cool and settle into a solid structure. If the sugar forms a few large crystals, then the candy texture will be coarse and grainy. If it forms many millions of microscopic crystals that are lubricated by just the right amount of syrup, then the candy will be smooth and creamy. And if it forms no crystals at all, then it will be a hard, monolithic mass. The trickiest stage of candy making thus comes after the cooking, when the syrup cools from 250–350ºF/ 120–175ºC down to room temperature. The rate of cooling, the movement of the syrup, and the presence of the smallest particles of dust or sugar can have drastic effects on the candy’s structure and texture.

How Sugar Crystals Form Sugar molecules have a natural tendency to bond to each other in orderly arrays and form dense solid masses, or crystals. When sugar crystals are dissolved in water to make a syrup, the water molecules overcome that tendency by forming their own bonds with the sugar molecules, surrounding and separating them from each other. If the dissolved sugar molecules in a syrup get too crowded for the water molecules to keep the sugars apart from each other, the sugars will begin to bond to each other again and form crystals. When the tendency of a dissolved substance to bond to itself is exactly balanced by the water’s ability to prevent this bonding, the solution is called saturated.

The saturation point depends on temperature. The rapidly moving water molecules in a hot sugar solution can keep more sugar molecules dissolved than the sluggish water molecules in a cold solution can. The moment that a hot and saturated solution begins to cool, it becomes super saturated. That is, it temporarily contains more dissolved sugar than it normally could at that temperature. And once the solution has become supersaturated, the smallest disturbance will induce sugar crystals to form and grow. As the sugar molecules gather into solid crystals, they leave the solution around them less concentrated. When the solution reaches the sugar concentration appropriate for its new temperature, the sugar crystals stop forming and growing. The sugar is now in two different states: some remains dissolved in the syrup, and some is packed in the solid crystals surrounded by the syrup.

There are two steps in sugar crystallization: the formation of crystal “seeds,” and the growth of those seeds into mature, full-sized crystals. Seed formation determines how many crystals will form, and crystal growth determines how large they get. Both steps affect the final texture of a candy.

The growth of sugar crystals as a hot syrup cools. Left: Crystals are tightly organized, solid clusters of molecules. Center: When conditions favor the formation of crystal seeds, the dissolved sugar molecules can join many seeds, the resulting crystals are small, and the candy texture is fine. Right: When conditions limit the formation of crystal seeds, the dissolved sugar molecules can join only a few seeds, the resulting crystals are large, and the candy texture is coarse.

Particles, Temperature, and Stirring Influence Crystallization The crystal “seed” is an initial surface to which sugar molecules can attach themselves and accumulate in a solid mass. The seed can be a few sugar molecules that happen to come together during random movements in the syrup. Stirring and agitation have the effect of bumping solution molecules together more often than they otherwise would, and thereby encourage the formation of crystal seeds. Other things can also serve as seeds in a cooling syrup and initiate crystallization. Among the more common are the tiny crystals that form when the syrup spatters on the side of the pan or dries off on a spoon, and that then are stirred back into the syrup. Dust particles and even tiny air bubbles can also act as crystal seeds. A metal spoon can induce crystallization by conducting heat away from local areas of the syrup, cooling them and so leaving them super-supersaturated. Experienced candy makers therefore prevent premature crystallization by using wooden spoons, avoiding agitation of the syrup once it’s cooked and begins to cool, and carefully removing dried syrup spatter from the pan walls with a moist brush.

Controlling Crystal Size and Candy Texture The cook has to worry about premature crystallization because candy texture is affected by the syrup temperature at which crystallization begins. Generally, hot syrups produce coarse crystals, and cool syrups produce fine crystals. Here’s the logic. Because more sugar molecules will arrive at the crystal surface during a given time in a hot syrup with fast-moving molecules than in a cold, lethargic one, crystals grow more rapidly in hot syrups. At the same time, because stable crystal seeds are less likely to form at higher temperatures — an aggregate of a few sugar molecules is more easily knocked apart in fast-moving surroundings — the total number of crystals formed in a hot syrup will be lower. Put these two trends together, and we see that when a hot syrup begins to crystallize, it will produce fewer and larger crystals than a cool one, and therefore a coarse texture. This is why recipes for fudge or fondant, candies with a fine, creamy texture, call for the syrup to be cooled drastically — from 235ºF/113ºC down to around 110ºF/43ºC — before the cook initiates crystallization by stirring.

Stirring Makes Smaller Crystals Crystal size and texture are also influenced by stirring. We’ve seen that agitation favors the formation of crystal seeds by pushing sugar molecules into each other. A syrup that is stirred infrequently will develop only a few crystals, while one that is kept in motion continuously will produce great numbers. And the more crystals there are in a syrup, all competing for the remaining free molecules, the fewer free molecules there are to go around, and so the smaller the average size of each crystal. The more a syrup is stirred, then, the finer the consistency of the final candy. This is the justification for wearing your arm out when making fudge: the moment you let up, the formation of seeds slows down, the crystals you’ve made up to that point begin to grow in size, and the candy gets coarse and grainy.

Preventing Crystal Formation: Making Sugar into a Glass Candy makers produce an entirely different structure and texture when they cool a syrup so rapidly that the sugar molecules stop moving before they have a chance to form any crystals at all. This is how transparent hard candies are made. If the water content of the cooked syrup is just 1 or 2%, then it’s essentially molten sugar with a trace of water dispersed in it. The syrup is very viscous, and if it cools quickly, the sucrose molecules never have a chance to settle into orderly crystals. Instead, they just set in place in a disorganized mass. Such an amorphous, noncrystalline material is called a glass. Ordinary window and table glass is a noncrystalline version of silicon dioxide. Like this mineral glass, sugar glass is brittle and transparent (and often stands in for its harder and more dangerous cousin in the movies and on stage!). Glasses are transparent because individual sugar molecules are too small to deflect light when they’re randomly arranged. Crystalline solids appear opaque because even tiny crystals are solid masses of many molecules, and their surfaces are big enough to deflect light.

Limiting Crystal Growth with Interfering Agents In practice, it’s not easy to control or prevent the crystallization of pure sucrose syrups, and candy makers have long relied on other ingredients that interfere with and therefore limit crystal formation and growth. These interfering agents help the cook prepare clear noncrystalline hard candies and fine-textured creams, fudges, and other soft candies.

Crystalline and glassy candies. Left: When a hot syrup cools slowly enough for the molecules to cluster together, they form tightly organized crystals. Right: When a very concentrated syrup cools quickly and traps the sugar molecules in place before they can cluster, they solidify into a disorganized, noncrystalline glass.

Invert Sugar The original interfering agents were glucose and fructose, or “invert sugar” (p. 655). When heated along with a small amount of acid (often cream of tartar), sucrose is broken down into its two components, glucose and fructose. Glucose and fructose interfere with sucrose crystallization by bonding temporarily to the crystal surface and blocking the way of sucrose molecules. Honey is a natural source of invert sugar, and “invert syrup” is an artificial preparation of a glucose-fructose mixture. Thanks to their fructose content, both honey and invert syrup readily caramelize and can cause undesirable browning in some sweets. Acid-inverted syrups brown less because their acidity slows caramelization.

Corn Syrup Because acid treatment of sucrose is somewhat unpredictable, most modern confectioners instead use corn syrup, which is an especially effective inhibitor of crystallization, and doesn’t readily caramelize. The assorted long glucose chains form a tangle that impedes the motion of both sugar and water molecules and makes it more difficult for the sucrose to find a crystal onto which to fit. The glucose and maltose molecules interfere in the same way that invert sugar does. Corn syrup also provides body and chewiness, is less sweet than sugars, and has the advantage for manufacturers of being less expensive than crystalline sugar.

Other Candy Ingredients Confectioners add a number of other ingredients to the basic sugar syrup for candies to modify taste and texture. All interfere with sucrose crystallization to some extent and so tend to encourage finer crystals.

Milk Proteins and Fat Milk proteins thicken candy body and, because they brown easily, add a rich flavor to caramels and fudge. The casein proteins contribute to a chewy body, whey proteins to browning and flavor development, and both help emulsify and stabilize butterfat droplets. Butterfat lends smoothness and moistness to butterscotch, caramel, toffee, and fudge, and reduces the tendency of chewy candies to stick to the teeth. Because milk proteins curdle in acid conditions, and caramelization and browning reactions generate acids, candies that include milk solids are sometimes neutralized with baking soda. The reaction between acids and baking soda generates bubbles of carbon dioxide, so such candies may be filled with small bubbles that give them a more fragile texture, less chewy or hard or clinging.

Gelling Agents Confectioners also give a firmer body to certain candies with a number of ingredients that bond to each other and to water to form solid but moist gels. These ingredients include gelatin, egg white, grain starches and flours, pectin, and plant gums. Gelatin and pectin in particular are used to make gummy and jelly candies, often in combination. Gelatin provides a tough chewiness, while pectin makes a more tender gel. Gum tragacanth, a carbohydrate from a West Asian shrub in the bean family (Astragalus), has been used for centuries to make the sugar dough from which lozenges are cut and dried.

Acids Many candies include an acid ingredient to balance the overwhelming sweetness. Jelly beans, for example, have a tart surface. These flavoring acids are added after the syrup has cooled down, so as to avoid excessive inversion of the sucrose into glucose and fructose. Different acids are said to have different taste profiles. Citric and tartaric acids give a rapid impression of acidity, while malic, lactic, and fumaric acids are slower to register on the tongue.

Kinds of Candies

It’s convenient to divide sugar confections into three groups: noncrystalline candies, crystalline candies, and candies whose texture is modified with gums, gels, and pastes. In practice these groups overlap: there are crystalline and noncrystalline versions of caramels, hard candies, nougat, sugar work, and so on. Here are brief descriptions of the principal candies made today.

Noncrystalline Candies:
Hard Candies, Brittles,
Caramel and Taffy, Sugar Work

Hard Candies Hard candies are the simplest noncrystalline candies; they include hard drops, clear mints, butterscotch, bonbons, lollipops, and so on. Hard candy is made by boiling the syrup high enough that the final solid will contain only 1 or 2% moisture, then pouring the syrup onto a surface and cooling it down, kneading in colors and flavors while it’s still malleable, and shaping it. The very high sugar concentration makes this syrup liable to form crystals at the slightest excuse, so a substantial proportion of corn syrup is used to prevent this and produce a clear sugar glass. The high cooking temperatures also encourage caramelization and a yellow-brown discoloration, which are not desirable in these candies; they’re often manufactured under reduced pressure, which allows them to reach the proper sugar concentration at a lower temperature.

Intentionally Crystalline Hard Candies The development of crystals is considered a defect in many hard candies, and results from too little interfering corn syrup, or the introduction of seed crystals from the pan sides, or too much moisture in the syrup. But some hard candies are intentionally manipulated to form tiny crystals, which give the candy a “short,” more crumbly texture. Candy canes and after-dinner mints are common examples of such confections. An opaque but satin-or silk-like sheen results when the cooled but malleable syrup is repeatedly pulled and folded back onto itself. This working incorporates some air bubbles, and these in turn encourage the formation of tiny sucrose crystals. Both bubbles and crystals interrupt the candy structure, giving it a crisp, light quality and making it easier to break between the teeth. (See “Sugar Work” below.)

Cotton Candy Cotton candy or candy floss is a very different kind of hard candy, filaments of sugar glass so fine that they have the consistency of a cotton ball and dissolve away the moment they touch the moist mouth. Cotton candy is made in a special machine that melts the sugar and forces it through tiny spinnerets into the air, where it instantly solidifies into threads. It was introduced at the 1904 World’s Fair in St. Louis.

Brittles Brittles are also cooked to a very low moisture content, around 2%, but unlike the other hard candies, they include butter and milk solids, and usually pieces of nuts. They’re thus opaque with fat droplets and protein particles, and brown in color thanks to extensive browning reactions between sugars and proteins. Baking soda is often added to brittle syrups after they’re cooked, for several reasons: alkaline conditions favor browning reactions, help neutralize some of the acids produced thereby, and the bubbles of carbon dioxide that result from this neutralization become trapped in the candy, giving it a lighter texture. The original French praline was a brittle made with almonds. (The modern New Orleans praline is soft and chewy, more like a caramel, and contains New-World pecans instead of almonds.)

Caramels, Toffees, and Taffies Caramels and their relatives are generally noncrystalline candies that contain milkfat and milk solids, usually in the concentrated form of sweetened condensed milk. (Cheap versions are made with milk powder and vegetable shortening.) They are chewy rather than hard, and wonderfully mouthwatering because chewing liberates droplets of butterfat from the sugar mass. Their chewiness comes from a lower cooking temperature and so a higher moisture content than hard candies, a large proportion of corn syrup, and the presence of milk casein proteins. The characteristic caramel flavor develops from the milk ingredients and reactions between these and the syrup sugars during the cooking. In Britain, butter for toffee was often stored to develop some rancidity (from free butyric acid), which produced a desirably stronger dairy flavor in the finished candy. (American chocolate manufacturers have done much the same thing; see box, p. 703). The higher the fat content, the less these candies stick to the teeth.

Caramels are cooked to the lowest temperature of the noncrystalline candies, have the highest moisture content, and are the softest. Toffees and taffies contain less butter and milk solids — taffies sometimes none at all — and are cooked 50ºF hotter than caramels, so they’re more firm. Taffies are often pulled to produce an aerated, finely crystalline, less dense, less chewy version. Caramels made with dairy products owe some of their flavor to caramelized sugar, but they include flavors from the Maillard reactions. Like the terminology, caramelized sugar and dairy flavors blend easily with each other. This may be in part because one of the important products of sugar caramelization is diacetyl, an aromatic chemical that provides the pronounced buttery aroma of cultured butter(p. 35). Caramel has a rich, complex flavor and consistency, viscous and sticky and creamy all at once, that works well with most sweets and fruits, with coffee and chocolate, and even with salt: the prized caramels of Brittany are made with a notable dose of sea salt.

Sugar Work The most spectacular sugar preparations are those that take advantage of sugar’s similarity to glass: its transparency and capacity to be sculpted, blown, and drawn out into countless shapes. “Sugar work,” as such preparations are called, goes back at least 500 years. A “nest of silken threads,” probably similar to our spun sugar, was made from malt syrup for the Chinese Imperial household before 1600; and in 17th-century Italy, various banquet decorations, including dishes, were made from sugar. In Japan, there is a traditional street entertainment called “sweet candy craft,” amezaiku, in which the performers sculpt flowers, animals, and other shapes while people watch.

The basic material for sugar work is molten sucrose mixed with a large portion of glucose and fructose to help prevent crystallization. The glucose and fructose may be added in the form of corn syrup, or the pure sugars, or they may be formed from the sucrose itself during the cooking of the syrup with added acid (cream of tartar). The sugar mixture is heated until it reaches 315–330ºF/157–166ºC, at which point there is practically no water left. Any residual water can cause crystallization and milkiness by making it easier for the sucrose molecules to move around and nest together. At somewhat higher temperatures, the sugar begins to caramelize and turn yellow-brown, which is undesirable for much sugar work but encouraged for spun sugar and sugar cages, which are made by drizzling the hot syrup in threads over a solid form or a wooden rack, where they harden almost instantly. For more elaborate sugar work, the entire sugar mass is cooled to around 130–120ºF/55–50ºC, a range in which it has a pliable, doughy consistency. Now it can be handled and formed, blown like glass into hollow spheres and other shapes, and kept workable with a heat lamp. Though pastry chefs with seasoned fingertips can sculpt sugar barehanded, many use thin latex gloves in order to avoid transferring moisture and skin oils from their fingers.

One of the more striking forms of sugar work is pulled sugar, which develops a lovely delicate satin-like opacity. The cook pulls a piece of the sugar mixture into a long rope, then folds and twists it onto itself and pulls again. By repeating this action many times, he forms the sugar mixture into many fine, partly crystalline strands separated by columns of air, a combination that becomes a solid fabric of shiny threads.

Crystalline Candies: Rock Candy, Fondant, Fudge, Panned Candies, Lozenges About the only candy in which large, coarse crystals are valued is rock candy, a vivid demonstration of crystal growth. Simply cook a syrup to the hard ball stage, then pour into a small glass, with a toothpick to serve as a removable foundation, and let it sit for a few days. The resulting crystals can be preserved by washing the encrusted stick briefly under cold water, shaking off the excess, and letting it dry.

Fondant and Fudge Fondant and fudge are the two most common finely crystalline candies, whose nature is to dissolve to a creamy consistency on the tongue. The name fondant comes from the French fondre, meaning “to melt,” and fondant is the base for what are called candy “creams,” the flavored, moist, melt-in-the-mouth interiors of filled chocolates and other candies. It also serves as an icing for cakes and pastries; it can be rolled out and molded onto a cake, or warmed or thinned until runny and poured into a thin layer. Fudge is essentially fondant made with added milk, fat, and sometimes chocolate solids (it can also be thought of as a crystallized version of caramel). Penuche is fondant made with brown sugar (some New Orleans pralines are penuche that includes pecans).

Fondant and fudge are made with the help of corn syrup, which favors the production of small crystals. After the syrup has been boiled and then cooled to 130–100ºF/54–38ºC, the cook beats it continuously for about 15 minutes, until crystallization is complete.

The texture of these candies depends on how much water they’re left with. If the syrup has become especially concentrated, the texture will be dry and crumbly, the appearance dull; if it’s less cooked or absorbs moisture from the air during cooling and beating, it will be soft, even runny, the appearance glossy thanks to the abundance of syrup between crystals. Small variations in water content — just 1 or 2% — make a noticeable difference. Fudge is more complex than fondant, its syrup carrying milk solids and fat droplets as well as sugar crystals.

Panned Candies These are the modern version of the medieval dragées: flavorful nuts or spices coated in sugar. There are two basic ways to coat candies in a pan. In hard panning, the nut or spice or other center is rolled around a hot pan and periodically sprayed with a concentrated sucrose syrup, whose moisture evaporates and leaves behind tightly interlocked, hard layers of crystals, just 0.01–0.02 mm thick. In soft panning, most often applied to jellybeans, the jelly candy is rolled around in a cool pan with a glucose syrup and powdered sugar. Instead of crystallizing, the syrup is absorbed by the powder, and excess moisture is dried off. Soft-panned layers are thicker and less crystalline.

Lozenges Lozenges are among the oldest and simplest of confections — they require no high-temperature cooking. They’re made by preparing a binding agent in water — gum tragacanth is standard, though gelatin also works — and then making a “dough” by adding finely ground icing sugar and flavoring. The dough is then rolled out, cut into pieces, and dried. Lozenges have a crumbly texture.

Aerated Candies: Marshmallow, Nougat Candies with a light, chewy texture are made by combining a sugar syrup with an ingredient that forms a stable foam. Egg whites, gelatin, and soy protein are the most common foaming agents. Usually they and interfering agents prevent the syrup from crystallizing, but some aerated candies are made crystalline by combining a fine fondant with the foam.

Marshmallows Marshmallows were first made in France from the gummy root juice of the marsh mallow (Althaea officinalis), a weedy relative of the hollyhock; the confection was called pâte de Guimauve. The juice was mixed with eggs and sugar and then beaten to a foam. Today, marshmallows are made by combining a viscous protein solution, usually gelatin, with a sugar syrup concentrated to about the caramel stage, and whipping the mixture to incorporate air bubbles. The protein molecules collect in the bubble walls, and this reinforcement, together with the viscosity of the syrup, stabilizes the foam structure. The gelatin accounts for 2–3% of the mixture, and produces a somewhat elastic texture. Marshmallows made with egg whites are lighter and softer.

Nougat Nougat is a traditional sugar candy made in Provence that contains nuts and is aerated with egg-white foam. Italian torrone and Spanish turron are similar. It’s a cross between a meringue and a candy, and is made by preparing a meringue and then streaming hot, concentrated sugar syrup into it while continuing to beat. It can be either soft and chewy or hard and crunchy depending on the degree to which the sugar syrup is cooked and the proportion of sugar syrup to egg white. Honey is often an ingredient.

Chewy Jelly and Paste Candies; Marzipan A number of different candies are made by incorporating a sugar syrup into a solution of starch, gelatin, pectin, or plant gums, and then allowing the mixture to solidify into a dense, chewy mass. In Japan and elsewhere in Asia, sweets are often gelled with the seaweed extract agar (p. 609), which is effective in unusually small amounts (as little as 0.1% of the mix).

Turkish Delight Turkish delight, or lokum rahat in Turkish, is one of the most venerable of this kind, having been made in the Middle East and the Balkans for centuries. It is thickened with starch (around 4%), translucent, and traditionally flavored with essence of rose.

Licorice Licorice is usually made with wheat flour and molasses, around 30% and 60% of the mix respectively, with licorice extract around 5%; it’s dense and opaque, like its flavor. The licorice is often complemented with anise, and in Scandinavian countries there’s a curious pairing of licorice with ammonia — in foods, an aroma usually encountered only in overripe cheeses!

Jelly Beans and Gummy Candies These favorites are made with approximately equal weights of sucrose and corn syrup and a mixture of gelatin and pectin. The gelatin may be between 5 and 15% of the candy weight, and by itself produces an increasingly elastic, even rubbery texture; pectin at around 1% introduces a complex microstructure into the candy, gives a shorter, more crumbly texture and also causes candy tastes and aromas to seem more intense. Gelatin is degraded in high heat, so a concentrated solution is added to the sugar syrup after it has been cooked and mostly cooled. These candies are relatively moist, being about 15% water.

Marzipan Marzipan is essentially a paste of sugar and almonds, has been made in the Middle East and Mediterranean region for centuries, and is especially prized as a sculptural material; it’s shaped and colored to resemble fruits and vegetables, animals, people, and many other objects. The solid phase in nut pastes like marzipan is provided by finely granulated sugar and the particles of nut proteins and carbohydrates. It can be made by cooking almonds and syrup together and then cooling and crystallizing the mixture; or ground almonds can be mixed with a premade fondant and powdered sugar. Egg white or gelatin is sometimes added to improve the binding.

Chewing Gum

This quintessentially American confection has ancient roots. Humans have chewed on gums, resins, and latexes secreted by various plants for thousands of years. The Greeks named the resin of a kind of pistachio tree with their word for “to grind the teeth together, to chew”: that was mastic (p. 421), whose root also gives us “masticate.” Europeans and North Americans chewed the relatively harsh resin of spruce trees; and the Maya chewed chicle, the latex of the sapodilla tree (Achras sapote), ten centuries before it was commercialized in New York City. The idea of mixing gum with sugar goes back to the early Arab sugar traders, who used the exudation of certain kinds of acacia, a substance now known as gum arabic. It and gum tragacanth are slightly soluble and eventually dissolve when chewed; they were used in early medicine as carriers that would release drugs slowly. This is still one of the purposes of chewing gum, which are to release a pleasant flavor for some time while giving the jaw muscles something to do and stimulating a cleansing flow of saliva.

Gum in America The history of modern chewing gums begins in 1869, when a New York inventor by the name of Thomas Adams was introduced to chicle from Central and South America. Chicle is a latex, a milky, water-based plant fluid that carries tiny droplets of long, coiled carbon-hydrogen chains. These chains have the property of being elastic: they uncoil and stretch out when pulled, but snap back when released. The best known of these latex substances is rubber. Adams got the idea of using the chicle as a gum base, and patented chicle gum in 1871. With sugar and sassafras or licorice flavorings, it quickly caught on. By 1900, entrepreneurs with such names as Fleer and Wrigley had developed gumballs and peppermint and spearmint flavors, and in 1928 a Fleer employee perfected bubble gum by developing a very elastic latex mixture from longer hydrocarbon polymers.

Modern Synthetic Gums Today, chewing gum is made mostly of synthetic polymers, especially styrene-butadiene rubber — also found in auto tires — and polyvinyl acetate — in adhesives and paints — though some brands still contain chicle or jelutong, a natural latex from the Far East. The crude gum base is first filtered, dried, and then cooked in water until syrupy. Powdered sugar and corn syrup are mixed in, then flavorings and softeners — vegetable oil derivatives that make the gum easier to chew — and the material is cooled, kneaded to an even, smooth texture, cut, rolled thin, and cut again into strips, and packaged. The final product is about 60% sugar, 20% corn syrup, and 20% gum materials. Sugar-free gums are made using sugar alcohols and intensive sweeteners (p. 659).

Candy Storage and Spoilage

Because of their generally low water content and concentrated sugars, which draw moisture out of living cells, candies are seldom spoiled by the growth of bacteria or molds. Their flavor can be degraded, however, by the oxidation and consequent rancidity of added fats, whether in milk solids or butter. This process can be slowed down by refrigeration or freezing, but cold storage encourages another problem called “sugar bloom.” Changes in temperature can cause moisture from the air to condense on the candy surface, and some sugar will dissolve into the liquid. When the moisture evaporates again or is drawn deeper into the candy, the surface sugar crystallizes into a rough, white coating. Airtight wrapping will prevent sugar bloom.

Chocolate

Chocolate is one of our most remarkable foods. It is made from the astringent, bitter, and otherwise bland seeds of a tropical tree, yet its flavor is exceptionally rich, complex, and versatile, the product of both fermentation and roasting. Its consistency is like no other food’s: hard and dry at room temperature, melting and creamy in the warmth of the mouth. It can be sculpted into almost any shape, and its surface can be made as glossy as glass. And chocolate is one of the few examples of a food whose full potential was first revealed in industrial manufacturing. The chocolate that we know and love, a dense, smooth, sweet solid, has existed for only a tiny fraction of chocolate’s full history.

The History of Chocolate

An Exotic Drink The story of chocolate begins in the New World with the cacao tree, which probably evolved in the river valleys of equatorial South America. The tree bears large, tough seed pods that also contain a sweet, moist pulp, and early peoples may have carried the pods into Central America and southern Mexico as a portable source of energy and moisture. It appears that the first people to cultivate the tree were the Olmecs of the southern Gulf coast of Mexico. They in turn introduced it sometime before 600 BCE to the Maya, who produced it in the tropical Yucatan peninsula and Central America, and traded it to the Aztecs in the cool and arid north. The Aztecs roasted and ground cacao seeds and made them into a drink that was served in religious ceremonies and associated with human blood. The seeds were valuable enough to serve as a form of currency. The first Europeans to see the cacao bean were probably the crew of Columbus’s fourth voyage in 1502, who brought some back to Spain. In 1519 one of Cortez’s lieutenants, Bernal Diaz del Castillo, saw the Aztec emperor Montezuma at table and in passing described the prepared drink:

One of the first detailed accounts of the original chocolate comes from the History of the New World (1564) by the Milanese Girolamo Benzoni, who traveled in Central America. He remarked that the region had made two unique contributions to the world: Indian fowls,” or turkeys, and “cavacate,” or the cacao bean.

Benzoni and other visitors reported that the Maya and Aztecs flavored their chocolate drinks with a number of different ingredients, including aromatic flowers, vanilla, chilli, wild honey, and achiote (p. 423). The Europeans then began to add their own flavorings, among them sugar, cinnamon, cloves, anise, almonds, hazel-nuts, vanilla, orange-flower water, and musk. According to the English Jesuit Thomas Gage, they dried the cocoa beans and spices, ground them up and mixed them together, and heated them to melt the cocoa butter and form a paste. Then they scraped the paste onto a large leaf or piece of paper, allowed it to solidify, and then peeled it off as a large tablet. According to Gage, there were several ways of preparing chocolate, both hot and cold.

The first European “factories” for making the spiced chocolate paste were built in Spain around 1580, and within 70 years chocolate had found its way into Italy, France, and England. These countries purged the drink of most added flavorings except sugar and vanilla. At first, vendors of lemonade sold it in Paris; coffeehouses — themselves an innovation — served it London. But by the late 17th century, chocolate houses were thriving in London as a kind of specialty coffeehouse. The idea of making hot chocolate from milk seems to have arisen in these places.

Early Chocolate Confections For a couple of centuries, Europe knew chocolate almost exclusively as a beverage. The use of the cacao bean in confectionery was quite limited. The Englishman Henry Stubbe noted in his treatise on chocolate, The Indian Nectar (1662), that in Spain and the Spanish colonies “there is another way of taking it made into Lozenges, or shaped into Almonds,” and that people were aware of what we now know to be the effects of the caffeine in chocolate: “The Cacao-nut being made into Confects, being eaten at night, makes Men to wake all night-long: and is therefore good for Souldiers, that are upon the Guard.” Cookbooks of the 18th century generally included a handful of recipes that call for chocolate, among them dragées, marzipans, and biscuits, creams and ices and mousses. There are some remarkable Italian recipes for lasagna sauced with almonds, walnuts, anchovies, and chocolate, for liver with chocolate, and polenta with chocolate. And in the 18th-century French Encyclopédie, we find that chocolat was commonly sold as a half-cocoa, half-sugar cake flavored with some vanilla and cinnamon, and was not so much a delightful confection as an emergency meal — perhaps the first instant breakfast!

Even in the middle of the 19th century, the English compendium Gunter’s Modern Confectioner devoted only four pages out of 220 to chocolate recipes.

Dutch and English Innovations: Cocoa Powder and Eating Chocolates The main reason for this lack of interest in solid chocolate was probably the coarse, crumbly texture of the chocolate paste. The suave confections that are so popular today were made possible by several innovations, the first of which came in 1828. Conrad van Houten, whose family ran a chocolate business in Amsterdam, was trying to find a way to make chocolate less oily so that the drink would be less heavy and filling. The weight of the cacao bean is better than half fat, or “cocoa butter.” Van Houten developed a screw press that removed most of the cocoa butter from the ground bean — in itself, not a novelty — and then sold the defatted cocoa powder, which carries nearly all the flavor, for making hot chocolate. Cocoa powder was a long-lasting success, though recently there has been a revival of interest in richer versions of hot chocolate full of cocoa butter.

At first, the pure cocoa butter extracted by Van Houten’s screw press was a mere by-product. But it turned out to be the key to the development of modern chocolate candy. This was cocoa butter that could be added to a paste of ordinary ground cocoa beans and sugar to provide a rich, melting matrix for the dry particles, and make the paste seem less pasty. The first solid “eating chocolate” was introduced by the English firm of Fry and Sons in 1847, and soon inspired many imitations throughout Europe and the United States.

Swiss Innovations: Milk Chocolate and Refined Texture In 1917, Alice Bradley’s Candy Cook Book devoted an entire chapter to “assorted Chocolates,” and noted that” more than one hundred different chocolates may be found in the price lists of some manufacturers.” The South American bean had come of age as a major ingredient in confectionery.

Two technical developments had helped expand chocolate’s appeal. In 1876, a Swiss confectioner named Daniel Peter used the new dried milk powder produced by his countryman Henri Nestlé to make the first solid milk chocolate. Not only do milk flavors blend well with chocolate, but the milk powder dilutes the strong chocolate flavor, and milk proteins reduce its astringency and make the taste milder. Today, most chocolate is now consumed in the form of milk chocolate. Then in 1878, a Swiss manufacturer named Rudolphe Lindt invented the conche, a machine which ground cacao beans, sugar, and milk powder slowly for hours and even days, and developed a much finer consistency than had been possible before. This is the consistency that we now take for granted in even the most ordinary chocolates.

Having contributed so much to the evolution of modern chocolate, the Swiss are understandably the world’s champion chocolate eaters, and have been so for a long time. At about an ounce/30 gm per day, Switzerland’s per capita consumption is nearly double that of the United States.

Making Chocolate

The transformation of the fresh cacao bean into a finished chocolate is an intriguing collaboration between the tremendous potential of the natural world and human ingenuity at finding nourishment and pleasure in the most unpromising materials. Right out of the pod, the bean is astringent, bitter, and essentially aroma-less. Cacao farmers and chocolate manufacturers develop its potential in several distinct processing steps:

• Farmers ferment the mass of beans and pulp in order to generate the precursors to chocolate flavor.
• Manufacturers roast the fermented beans to transform flavor precursors into flavors.
• Manufacturers grind the beans, add sugar, and then physically work the mixture to refine its flavor and create a silken texture.

The Cacao Bean The cacao tree, named Theobroma cacao by Linnaeus — theobroma is Greek for “food of the gods” — is a broad-leaved evergreen that grows between 20º north and south of the equator, and reaches about 20 feet/7 m in height. It produces fruits in the form of fibrous pods from 6 to 10 inches/15–25 cm long, 3 or 4 inches/7.5–10 cm in diameter, and containing 20 to 40 seeds, or “beans,” each about an inch/2.5 cm long, embedded in a sweet-tart pulp.

Varieties There are a number of different cacao varieties that fall into three botanical groups: the Criollos, Forasteros, and Trinitarios. Criollo trees produce relatively mild beans with some of the finest, most delicate flavors, reminiscent of flowers and tea. Unfortunately, they are also disease-prone, low-yielding trees, and so provide less than 5% of the world crop. High-yielding, robust Forasteros provide most of the world’s cacao crop in the form of full-flavored “bulk” beans. Trinitarios are hybrids of a Criollo and Forastero, and have intermediate qualities.

West Africa (Ivory Coast and Ghana) now accounts for more than half of world cacao production, and Indonesia also out-produces Brazil, the largest producer in cacao’s original homeland.

Storage and Defensive Cells Cacao beans consist mainly of the embryo’s storage leaves, or cotyledons (p. 453), and contain two distinct groups of cells. Around 80% of the cells are storage depots of protein and of fat, or cocoa butter, nutrients that will feed the seedling as it germinates and develops on the shady floor of the tropical forest. The other 20% are defensive cells meant to deter the many forest animals and microbes from feasting on the seed and its nutrients. These cells are visible in the cotyledons as purplish dots, and contain astringent phenolic compounds, their chemical relatives the anthocyanin pigments, and two bitter alkaloids, theobromine and caffeine. The beans are moist, around 65% water. The composition of the dried fermented beans is shown in the box on p. 698.

Fermentation and Drying The first important step in the development of chocolate flavor is the least controlled and predictable. Fermentation takes place where cacao is grown, on thousands of small farms and larger plantations, and may be done carefully or casually or not at all, depending on the resources and skill of the farmer. The quality of cacao beans thus varies tremendously, from unfermented to badly overfermented and even moldy. The first challenge for the chocolate manufacturer is to find good-quality, fully fermented beans.

Soon after the cacao pods are harvested, workers break them open and pile the beans and sugary pulp together at the ambient tropical temperature. Microbes immediately begin growing on the sugars and other nutrients in the pulp. A proper fermentation lasts from two to eight days, and generally has three phases. In the first, yeasts predominate, converting sugars to alcohol and metabolizing some of the pulp acids. As the yeasts use up the oxygen trapped in the pile, they are succeeded by lactic acid bacteria, many of which are the same species found in fermented dairy products and vegetables. When workers turn the mass of beans and pulp to aerate it, the lactic bacteria are succeeded by acetic acid bacteria, the makers of vinegar, which consume the yeasts’ alcohol and convert it into acetic acid.

Cacao pods contain many large seeds that are covered with a sweet pulp. The seeds consist mainly of the embryo’s tightly folded food-storage cotyledons, which are speckled with purple defensive cells rich in alkaloids and astringent phenolic compounds.

Fermentation Transforms the Beans Cacao fermentation is a fermentation of the pulp, not the beans, but it transforms the beans as well. The acetic acid produced by the vinegar bacteria penetrates into the beans and etches holes in cells as it does so, spilling the contents of the cells together and allowing them to react with each other. The astringent phenolic substances mix with proteins, oxygen, and each other, and form complexes that are much less astringent. Most important, the beans’ own digestive enzymes mix with the storage proteins and sucrose sugar and break them down into their building blocks — amino acids and simple sugars — which are much more reactive than their parent molecules, and will produce more aromatic molecules during the roasting process. Finally, the perforated beans soak up some flavor molecules from the fermenting pulp, including sugars and acids, fruity and flowery and winey notes. So a properly conducted fermentation converts the astringent but bland beans into vessels laden with desirable flavors and flavor precursors.

Drying Once fermentation is complete, the cacao farmers dry the beans, often just by spreading them out on a flat surface in the sun. Drying can take several days, and if not done carefully can allow undesirable bacteria and molds to grow both on and within the beans and taint them with undesirable flavors.

Once dried to about 7% moisture, the beans are resistant to further microbial spoilage. They’re then cleaned, bagged, and shipped to manufacturers all over the world.

Roasting Dried fermented cacao beans are less astringent and more flavorful than unfermented beans, but their flavor is still unbalanced and undeveloped, and often dominated by vinegary acetic acid. After selecting, sorting, and blending the dried beans, the chocolate manufacturer roasts them to develop their flavor. The time and temperature vary according to whether the beans are to be roasted whole, in their thin shell, or as the cracked inner kernels, the nibs, or as nibs that have been ground into small, quickly heated particles. Whole beans take 30–60 minutes at 250–320ºF/ 120–160ºC. This is a much gentler treatment than coffee beans require, thanks to the abundance of reactive amino acids and sugars that readily participate in Maillard browning to generate flavor (p. 778). In fact, gentle roasting helps preserve some of the flavors that are intrinsic to the beans or developed during fermentation.

Grinding and Refining After roasting, the beans are cracked open and the nibs are separated from the shells. The nibs are then passed between several sets of steel rollers, and are transformed from solid chunks of plant tissue into a thick, dark fluid called cocoa liquor. This grinding stage has two purposes: to break the bean cells open and release their stores of cocoa butter; and to break the cells down into particles too small for the tongue to detect as separate, gritty grains. Because the nibs are around 55% cocoa butter, this fat becomes the continuous phase, and the solid fragments of the cells — mainly protein, fiber, and starch — are suspended in the fat. The final grinding, or refining, brings the particle size down to 0.02–0.03 mm. Swiss and German chocolates have traditionally been ground smoother than English and American.

Further treatment of the cocoa liquor varies according to the manufacturer’s needs. To make cocoa powder and cocoa butter, the liquor is pressed through a fine filter that retains the cocoa particles while allowing the butter to flow through. The compacted cake of cocoa particles is then made into cocoa powder (below), while the butter becomes an important ingredient in all kinds of manufactured chocolate.

Conching Pure cocoa liquor has a concentrated chocolate taste, and may be hardened and packaged as is for use in baked goods. But its flavor is relatively rough, bitter, and astringent and acidic. To make it into something not only edible but delicious, manufacturers add a few other ingredients: sugar for dark chocolate, sugar and dry milk solids for milk chocolate, some vanilla (the whole bean, or an extract, or artificial vanillin), and a supplement of pure cocoa butter. And they subject the mixture to an extended agitation called conching, a process named after the shell-like shape of the first machines. Conches rub and smear the mixture of cocoa liquor, sugar, and milk solids against a solid surface. The combination of friction and supplemental heat raises the temperature of the mass to 115–175ºF/45–80ºC (milk chocolate is kept at 110–135ºF/43–57ºC). Depending on the machine and manufacturer, conching may last for 8 to 36 hours.

Refining Texture and Flavor The original conche was a mechanized version of the Mayan stone grinding slab: a heavy granite roller moved back and forth over a granite bed, both mixing the ingredients together and grinding the still somewhat coarse particles to a finer size. Today the various solids are ground to the proper dimensions before conching, which now serves two main functions. First, it breaks up small aggregates of the solid particles, separates them from each other, and coats all of them evenly with cocoa butter, so that when the finished chocolate melts, it flows smoothly. Second, conching greatly improves the flavor of the chocolate, not by heightening it, but by mellowing it. The aeration and moderate heat causes as much as 80% of the volatile aromatic compounds (and excess moisture) to evaporate out of the chocolate liquor. Fortunately, many of these are undesirable volatiles, including various acids and aldehydes; acidity steadily declines during conching. At the same time, a number of desirable volatiles are augmented by the heat and mixing, notably those with roasted, caramel, and malty aromas (pyrazines, furaneol, maltol).

Both cocoa butter and a small amount of the emulsifier lecithin (p. 802) are added to the chocolate mass toward the end of conching. The additional cocoa butter is necessary to provide sufficient lubrication for all the added sugar particles to make the mixture creamily fluid rather than pasty when it melts. The higher the ratio of sugar to ground nibs, the more added cocoa butter is required. Lecithin, whose use in chocolate dates to the 1930s, coats the sugar particles with the fat-like ends of its molecules and helps reduce the amount of cocoa butter needed to lubricate the particles; one part of lecithin replaces 10 parts of butter. It typically makes up 0.3–0.5% of chocolate weight.

Cooling and Solidifying After conching, dark chocolate is essentially a warm fluid mass of cocoa butter that contains suspended particles of the original cacao beans and of sugar. Milk chocolate also contains butterfat, milk proteins, and lactose, and proportionally less cacao bean solids.

The last step in manufacturing chocolate is to cool the fluid chocolate to room temperature and form the familiar solid bars. It turns out that this transition from fluid to solid is a tricky one. To obtain stable cocoa butter crystals and a glossy, snappy chocolate, manufacturers carefully cool and then rewarm the liquid chocolate to particular temperatures before portioning it into molds, where it finally cools to room temperature and solidifies.

Cooks often melt manufactured chocolate in order to give it a special shape or to coat other foods. If they want it to resolidify with its original gloss and snap, then they must repeat in the kitchen this cycle of warming up and cooling down, or tempering (p. 709).

The composition of dark and milk chocolates. Left: Dark chocolate consists of cacao-bean particles and sugar crystals embedded in a base of cocoa butter. Right: In milk chocolate, a significant proportion of cacao-bean particles is replaced with particles of dried milk protein and sugar.

OPPOSITE: Making chocolate. As is true of cane sugar, chocolate is processed in two stages, the first in the tropical cacao-growing countries and the second in manufacturing plants throughout the world.

The Special Qualities of Chocolate

Consistency and Appearance: The Creations of Cocoa Butter The remarkable appearance and consistency of chocolate are a direct expression of the physical qualities of cocoa butter, the part of chocolate that surrounds the solid particles of cacao bean and holds them together. When carefully prepared, chocolate has a silken or glassy surface, is hard and not greasy at room temperature, breaks with a delightful snap, yet melts to a smooth creaminess in the mouth. These are very unlike the qualities of any other food, and are a consequence of the structure of cacao fat molecules, which are mostly saturated and unusually regular (most of them are constructed from just three kinds of fatty acids). This structure means that the fat molecules are capable of forming a dense network of compact, stable crystals, with little liquid fat left over to ooze out between the crystals.

However, this special network only develops when the fat crystallization is carefully controlled. Cocoa butter can solidify into six different kinds of fat crystals! Only two are stable kinds that produce a glossy, dry, hard chocolate; the other four are unstable kinds that produce a looser, less organized network, with more liquid fat, and crystals whose fat molecules readily detach and ooze away. When chocolate melts and then resolidifies in an uncontrolled way — for example, when it’s temporarily left too close to a hot stove, or in a hot car — it’s the unstable crystals that predominate, and they produce a greasy, soft, mottled chocolate. To rescue its original consistency, such chocolate must be tempered.

The crystallization of cocoa butter. Left: In melted chocolate, the fat molecules (p. 798) of cocoa butter are in constant random motion. Center: When chocolate cools in an uncontrolled way, the fat molecules form loosely packed, unstable crystals, and the chocolate is soft and greasy. Right: When chocolate is carefully cooled, its fat molecules form tightly packed, stable crystals, and the chocolate is snappy and dry.

Chocolate Flavor Chocolate has one of the richest and most complex flavors of any food. In addition to its slight acidity, pronounced bitterness and astringency, and the sweetness of its added sugar, chemists have detected more than 600 different kinds of volatile molecules in chocolate. While a handful of these may account for the basic roasted quality, many others contribute to its depth and wide range. The richness of chocolate flavor arises from two factors. One is the cacao bean’s intrinsic flavor potential, its combination of sugars and proteins, and the enzymes that break these down into the building blocks of flavor. The second factor is the complexity of chocolate’s preparation, which combines the chemical creativity of microbes and of high heat.

Among the flavors that an attentive taster can detect in chocolate are these:

• From the bean itself, astringency and bitterness (phenolic compounds, theobromine)
• From the fermented pulp, the flavors of fruits and wine and sherry and vinegar (acids, esters; alcohols; acetaldehyde; acetic acid)
• From the self-digested bean, almond and dairy and flowery notes (benzaldehyde; diacetyl and methyl ketones; linalool)
• From roasting and the browning reactions, roasted, nutty, sweet, earthy, flowery, and spicy notes (pyrazines and thiazoles; phenyls; phenylalkanals; dienals), as well as a more pronounced bitterness (diketopiperazines)
• From added sugar and vanilla, sweetness and the warm character of the spice
• From added milk solids, caramel and butterscotch and cooked-milk and cheese notes

Chocolate made from poorly fermented or handled beans can have a variety of unpleasant aromas, among them rubbery, burned, smoky, hammy, fishy, moldy, cardboard, and rancid notes.

Some confectioners add a small amount of salt to their products, especially milk chocolates. Saltiness is the one basic taste sensation missing from simply sweetened chocolate, and adding it is said to give the overall flavor a certain bite and clarity.

The Kinds of Chocolate

Manufacturers produce a wide range of different chocolates, some meant for eating as is, some meant for cooking or confectionery, some for all three. They fall into several general categories.

• Mass-produced, inexpensive chocolates are made from ordinary beans that are processed in largely automated plants, and contain the minimum amount of cocoa solids and cocoa butter and the maximum amounts of sugar and milk solids. Their flavor is mild and unremarkable.
• “Fine” expensive chocolates are made from beans selected for their excellent flavor potential, often processed in small batches to optimize flavor development, and contain far more than the minimum amount of cocoa solids and cocoa butter. Their flavor is stronger and more complex.
• Dark chocolate contains cocoa solids, cocoa butter, and sugar, but no milk solids. It is manufactured in a range of compositions, from sugarless bitter, to bittersweet, to sweet. Some manufacturers now label their premium chocolates with their content of cocoa beans: “70% chocolate” is 70% by weight cocoa butter and cocoa solids, and about 30% sugar; “62% chocolate” is about 38% sugar (there are also small amounts of lecithin and vanilla). The higher the proportion of cocoa solids, the more intense the chocolate flavor, including its bitterness and astringency. Strong chocolates deliver more flavor to cream, egg, and flour mixtures, whose proteins bind to the phenolic substances and reduce the apparent astringency.
• Milk chocolate is the most popular form of chocolate, and the mildest. It contains milk solids and a large proportion of sugar, which together usually outweigh the combination of cocoa solids and cocoa butter. Thanks to its relatively low cocoa butter content, milk chocolate tends to be softer and less snappy than bittersweet chocolate.
• Couverture chocolate (from the French for “to cover”) is dark or milk chocolate formulated to flow easily when melted, and therefore to work well for forming thin, delicate chocolate coatings. This means adding more cocoa butter than usual to provide plenty of room for the cocoa and sugar particles to move past each other. Most couvertures are 31–38% fat.
• “White chocolate” is chocolate-less chocolate: it contains no cocoa particles whatsoever, and therefore has little or no chocolate flavor. White chocolate was invented around 1930, and is a mixture of purified, usually deodorized cocoa butter, milk solids, and sugar. It does offer a valuable decorative contrast to ordinary chocolate.

Some manufacturers are now packaging nibs, or small pieces of the roasted beans, which offer crunchy particles of intense flavor. Whole roasted beans can sometimes be found in Latin markets.

Storing Chocolate; Fat Bloom The best storage temperature for chocolate is a constant 60–65ºF/15–18ºC, without fluctuations that would encourage the melting and recrystallization of the cocoa butter fats. Sometimes stored chocolate will develop a white, powdery-looking coating on its surface. This “fat bloom” is cocoa butter that has melted out of unstable crystals, migrated to the surface, and formed new crystals there. Fat bloom is normally prevented by proper tempering of the chocolate in the first place. Its development can be slowed down by the addition to the melted chocolate of some clarified butter, which makes the mix of fats more random and so retards the formation of crystals.

Thanks to its abundant antioxidant molecules and chemically stable saturated fats, chocolate has a remarkably long shelf life. It keeps for many months at room temperature. White chocolate, which lacks the antioxidants in the cocoa solids, has a room-temperature shelf life of only a few weeks; after that, or sooner if it’s exposed to bright light, its fats are damaged and it develops a stale, rancid flavor.

Cocoa Powder Manufacturers produce cocoa powder from the cakes of roasted cocoa bean particles left behind when they extract cocoa butter (p. 699). The particles remain coated with a thin layer of cocoa butter; the fat content of the powder ranges from 8 to 26%. The solid particles of the cacao bean are the source of chocolate’s flavor and color. Cocoa is therefore the most concentrated version of chocolate, and a valuable ingredient in its own right. Natural cocoa powder has a strong chocolate taste and pronounced astringency and bitterness. It’s also distinctly acid, with a pH around 5.

“Dutched” or Alkalized Cocoa In Europe and sometimes the United States, cocoa powder is produced from cocoa beans that have been treated with an alkaline substance, potassium carbonate. This treatment, sometimes called “dutching” because its inventor was the Dutch chocolate pioneer Conrad van Houten, raises the cocoa pH to a neutral 7 or alkaline 8. The application of an alkaline material to the beans either before or after roasting has a strong influence on their general chemical composition. In addition to adding a distinctly alkaline taste (like that of baking soda), alkaline treatment reduces the levels of roasty, caramel-like molecules (pyrazines, thiazoles, pyrones, furaneol) and of astringent, bitter phenolics, which now bond to each other to form flavorless dark pigments. The result is a cocoa powder with a milder flavor and darker color. Dutched cocoa can be produced in shades running from light brown to nearly black; the darker the color, the milder the flavor.

Cocoas in Baking It’s important for bakers to be aware of the difference between “natural” and alkalized cocoa powders. Some recipes rely on acidic natural cocoa to react with baking soda and generate leavening carbon dioxide. If the same recipe is made with an alkalized cocoa, the reaction won’t take place, no carbon dioxide will be generated, and the taste will be alkaline and soapy.

Instant Cocoa So-called “instant” cocoas for hot chocolate include lecithin, an emulsifier that helps separate the particles so that they mix readily with water. Sugar is frequently added to instant cocoa mix and may account for up to 70% of its weight.

Chocolate and Cocoa as Ingredients

Chocolate and cocoa are versatile ingredients. They’re incorporated into many mixtures of ingredients, and not just sweets; savory Mexican mole sauces and some European meat stews and sauces borrow depth and complexity from them. Chocolate and cocoa provide flavor, richness, and structure-building capacity; their dry particles contain both starch and protein, absorb moisture, and contribute thickness and solidity to baked goods, soufflés, fillings and icings. Flourless cakes can be made with chocolate or cocoa as the starchy and fatty ingredients, eggs as the moistening and setting agent. In a chocolate mousse, the foam structure provided by the whipped eggs is reinforced by both the dry particles and the gradually crystallizing cocoa butter.

Of course, chocolate can be presented as is, part of a pastry construction for example, or melted over a preparation and then hardened to provide a coating. It’s when we melt and cool it for coating or molding that it requires the most care (p. 708). Otherwise, keeping in mind a few facts about chocolate will prevent most problems.

Working with Chocolate Dark chocolate is a fully cooked, fully developed ingredient in its own right, robust and forgiving. Remember that it has been roasted and then heated again to fairly high temperatures in the conche, and that it’s a relatively simple physical mixture of cocoa and sugar particles in fat. The most that a cook needs to do to it is melt it to perhaps 120ºF/50ºC, but it can be heated to 200ºF/93ºC and then some without suffering disastrous effects. It won’t separate, and it won’t burn unless it’s left over direct stovetop heat or in a microwave oven without stirring. It can be melted and solidified repeatedly if necessary.

Because they contain more milk solids than they do cocoa solids, milk chocolate and white “chocolate” are less robust than dark chocolate and are best melted gently.

Melting Chocolate Chocolate can be successfully melted in several different ways: quickly, over direct stove heat, with care and constant stirring to avoid burning; more slowly, but with less attention; in a bowl set over a pan of hot water, from 100ºF/38ºC to the simmer (the hotter the water, the faster it melts); in the microwave oven, with frequent interruptions for stirring and checking the temperature. Because chocolate is a poor heat conductor, it’s best to chop it into small pieces or process it into crumbs to speed its melting, or its blending with hot ingredients.

Chocolate and Moisture The one vulnerable aspect of chocolate is its extreme dryness, and the vast number of tiny sugar and cacao particles whose surfaces attract moisture. If a small amount of water is stirred into molten chocolate, the chocolate will seize up into stiff paste. It seems perverse that adding liquid to a liquid produces a solid: but the small amount of water acts as a kind of glue, wetting the many millions of sugar and cocoa particles just enough to make patches of syrup that stick the particles together and separate them from the liquid cocoa butter. It’s important, then, either to keep chocolate completely dry, or to add enough liquid to dissolve the sugar into a syrup, not just wet it. It’s therefore best to add solid chocolate to hot liquid ingredients, or pour the hot liquid all at once onto the chocolate, rather than add the liquid gradually to molten chocolate. Seized chocolate can be salvaged by adding more warm liquid until the paste turns into a thick fluid.

Different Chocolates Are Not Interchangeable Both recipe writers and cooks need to be as precise as possible about the kinds of chocolate they use. Different chocolates have very different proportions of cocoa butter, cocoa particles, and sugar. The proportions of cocoa particles and sugar are especially important when chocolate is combined with wet ingredients. Sugar dissolves into syrup, thereby increasing the volume of a preparation’s liquid phase and contributing fluidity, while cocoa particles absorb moisture, decrease the volume of the liquid phase, and reduce fluidity. A recipe developed for sweet chocolate may fail badly if it’s made with a 70% premium bittersweet chocolate, which has far more drying cocoa particles and far less syrup-making sugar.

Ganache Once of the simplest and most familiar of chocolate preparations is ganache, a mixture of chocolate and cream that can be infused with many other flavors, whipped to lighten its richness, or further enriched with butter. It serves as a filling for chocolate truffles and pastries, and as both filling and topping for cakes. The dessert called pot de crème, made by melting some chocolate into about twice its weight of cream, is essentially a ganache served on its own.

Ganache Structure A soft ganache is made with approximately equal weights of cream and chocolate. A firm ganache, more suitable for holding a shape and with a stronger chocolate flavor, is made with two parts chocolate for every one of cream. To make ganache, the cream is scalded and the chocolate melted into it to form a complex combination of an emulsion and a suspension (p. 818). The continuous phase of this mixture, the portion that permeates it, is a syrup made from the cream’s water and the chocolate’s sugar. Suspended in the syrup are the milk fat globules from the cream, and cocoa butter droplets and solid cocoa particles from the chocolate.

In an even mixture of cream and chocolate, there’s an abundance of the syrup phase to hold the fat and particles; but in a firm, high-chocolate mixture, there’s less syrup, and proportionally more cocoa particles that slowly absorb moisture from the syrup and reduce its volume even further. With chocolates high in cocoa solids, the cocoa particles can eventually absorb so much moisture that they swell and stick to each other. The water-deprived emulsion then fails, allowing the fat globules and droplets to coalesce, and the fat to separate from the swollen particles. This is why high-chocolate ganaches are often unstable and coarsen with time.

Maturing Ganache Many confectioners let ganache mixtures stand at a cool room temperature overnight before working with them. This gradual cooling allows the cocoa butter to crystallize so that when the ganache is shaped or eaten, it softens and melts more slowly. Ganache refrigerated immediately after making hardens without forming many crystals, and becomes soft and greasy when it warms.

Thanks to the initial scalding of the cream and the chocolate’s sugar content, moisture-absorbing cocoa particles, and abundant microbe-unfriendly phenolic compounds, ganache has a surprisingly long shelf life of a week or more at room temperature.

Tempered Chocolate for Coating and Molding

Like sugar, chocolate can be shaped to please the eye. Pastry cooks and confectioners make thin chocolate sheets by brushing melted chocolate onto a surface, then letting the chocolate set completely, and stamping or cutting it into shapes, or nudging it into a ruffle. Melted chocolate can be painted onto plant leaves, allowed to harden into the leaves’ mirror images, then gently peeled off. It can be squeezed through a pastry bag and tip to form a myriad of lines, drops, and filled shapes. And of course it can be used to line molds and produce shapes from hollow spheres to Easter bunnies.

Chocolate lovers often melt chocolate and then use it as a coating for cookies or strawberries or handmade truffles. This can be done easily and casually, the chocolate simply warmed until it melts and then used immediately, the results sometimes chilled in the refrigerator to speed their solidification. Chocolate handled in this way will taste fine, but it’s likely to look dull and mottled, and to be soft instead of snappy. This is because the chocolate cooled down so quickly that its cocoa fat solidified into a loose, weak network of unstable crystals instead of the dense, hard network of stable crystals. If appearance and consistency matter, as they do to professional cooks and confectioners, then the cook must temper the melted chocolate, or prime it with desirable stable crystals of cocoa fat, just as the manufacturer did before forming it into bars.

The structure of ganache. Left: Soft ganache is made with an equal proportion of chocolate and cream, with cocoa particles and droplets of cocoa and milk fat surrounded by a syrup of the chocolate’s sugar and the cream’s water. Center: A firm ganache, made with more chocolate than cream, contains proportionally more dry cocoa particles and less water. Right: With time, the cocoa particles in a firm ganache absorb water from the syrup and swell. This can crowd the fat droplets so tightly that they coalesce and the ganache separates.

Tempering Chocolate The tempering process consists of three basic steps: heating the chocolate to thoroughly melt all of its fat crystals, cooling it somewhat to form a new set of starter crystals, and carefully heating it again to melt the unstable crystals, so that only desirable stable crystals remain. The stable starter crystals will then direct the development of the dense, hard crystal network when the chocolate finally cools and solidifies.

Unstable cocoa butter crystals are crystals that melt relatively easily, which means at relatively cool temperatures, between about 59 and 82ºF/15–28ºC. The desirable stable crystals (sometimes referred to as “beta” or “beta prime” or “Form V” crystals) melt only at warmer temperatures, between 89 and 93ºF/32–34ºC. The temperature range in which a particular kind of crystal melts is also the range in which it forms as the chocolate cools. Unstable crystals therefore form when molten chocolate is cooled rapidly, so that the stable crystal types — the ones that begin to form at warmer temperatures — don’t have time to gather most of the fat molecules to themselves before the unstable crystals begin to form. Stable crystals predominate in melted chocolate when the cook carefully holds it at temperatures above the melting point of the unstable crystals, but below the melting point of the stable crystals. This tempering range is 88–90ºF/31–32ºC for dark chocolate, somewhat lower for milk and white chocolates thanks to their mixture of cocoa and milk fats.

Tempering Methods There are several different ways to obtain melted chocolate that is in temper. All of them require an accurate thermometer, a gentle heat source (often a pot of hot water over which the bowl of chocolate can be held), and the cook’s full attention. And all of them end with the chocolate at a temperature where stable crystals can form and unstable crystals can’t.

Of the two common methods for tempering chocolate, one creates the stable crystals from scratch, while the other uses a small amount of tempered chocolate to “seed” the melted chocolate with stable crystals.

• To temper the chocolate from scratch, heat it to 120ºF/50ºC to melt all crystals, and cool it down to around 105ºF/40ºC. Then either stir the chocolate as it cools further, until it thickens noticeably (an indication of crystal formation), or pour a portion onto a cool surface and scrape and mix it until it thickens, and return it to the bowl. Then carefully raise the temperature of the chocolate to the tempering range, 88–90ºF/31–32ºC, and stir to melt any unstable crystals that might have formed during the stirring or scraping.
• To seed melted chocolate with stable crystals, chop and hold in reserve a portion of solid tempered chocolate. Heat the chocolate to be tempered to 120ºF/50ºC to melt all crystals, and cool it to 95–100ºF/35–38ºC, just above the temperature range in which stable crystals form. Then stir in the solid portion with its stable crystals, while keeping the temperature in the tempering range, 88–90ºF/31–32ºC.

No matter how chocolate is tempered, its temperature must be held in the tempering range until it is used. If allowed to cool, it will begin to solidify prematurely, won’t flow evenly, and produces an uneven consistency and appearance.

Melting Tempered Chocolate While Maintaining It in Temper It’s also possible to obtain tempered melted chocolate without actually doing the tempering. Nearly all manufactured chocolate is sold in tempered form. A cook using new, well-made chocolate can warm it carefully and directly to the tempering range, 88–90ºF/31–32ºC, so that it melts but still retains some of its desirable fat crystals. This is easily done by stirring the finely chopped chocolate in a bowl over a pot filled with water at 90–95ºF/32–34ºC. If for some reason the chocolate is overheated, so that it loses all of its fat crystals, or if the cook is using previously melted and resolidified chocolate with a mixture of crystals, then it’s necessary to temper the chocolate with one of the methods described above.

Tempering chocolate. To make chocolate with stable fat crystals, the cook first heats the chocolate to melt all the crystals. In one method, he then cools the chocolate to the temperature range in which only stable crystals can form, adds a portion of tempered chocolate to provide stable crystal seeds, and keeps the mixture warm until it’s used for molding or coating. In a second method (dotted line) , the cook allows the molten chocolate to cool below the stable-crystal temperature and form a mixture of crystal types, then warms it to melt the unstable crystals while retaining the stable ones.

The Art of Tempering Though an accurate thermometer and careful temperature control are necessary for successful tempering, they aren’t sufficient. The art of tempering lies in recognizing when the chocolate has accumulated enough stable crystals to form a dense, hard network as it cools. Insufficient tempering time, or insufficient stirring, produce too few stable crystal seeds and undertempered chocolate, which will form some unstable crystals when it cools. Too much stirring or time produce too many or too large stable crystals and overtempered chocolate, in which individual crystals predominate over the joined network. Overtempered chocolate is stable, but it can seem coarse, crumbly rather than snappy, dull in appearance, and waxy in the mouth.

Testing for Temper Molten chocolate can be tested for its temper by placing a small, thin portion on a room-temperature surface, a plate or piece of foil. Properly tempered chocolate solidifies in a few minutes to a clean, silky-surfaced mass; the side in contact with the cool surface is shiny. Chocolate out of temper takes many minutes to harden, and has an irregular powdery or grainy appearance.

Working with Tempered Chocolate Once chocolate has been tempered, it must be handled so that it stays in temper. It should be kept warm, in the tempering range of 88–90ºF/31–32ºC. When shaped, it should be poured into molds or coated onto fillings that are neither so cold that they cause the cocoa butter to solidify quickly and unstably, nor so warm that they melt the stable crystal seeds in the chocolate. Confectioners recommend a temperature around 77ºF/25ºC. Similarly, the room temperature should be moderate, neither chilly nor hot.

It turns out that tempered chocolate shrinks by about 2% in each dimension as it solidifies, because the fat molecules in the stable crystals are more densely packed than they were in liquid form. This shrinkage is helpful in making molded chocolates, because the chocolate pulls away from the mold as it hardens. But it can cause the thin coating on a candy or truffle to crack, especially if the filling is cold and expands slightly when coated with the warm chocolate. The snappy hardness of tempered chocolate takes several days to develop fully as the crystal network continues to grow and become stronger.

Modeling Chocolate “Modeling” or “molding” chocolate is a version made expressly for shaping into decorations. It’s made by mixing molten chocolate with a third to half its weight of corn syrup and sugar, then kneading the mixture into a pliable mass. The resulting “chocolate” is now a concentrated sugar syrup that is filled and thickened with cocoa particles and droplets of cocoa butter. The pieces stiffen as the syrup phase loses moisture to the air and to the dry cocoa particles.

Chocolate and Health

Fats and Antioxidants Cocoa beans, like all seeds, are rich in nutrients that support the plant embryo until it develops leaves and roots. They’re especially rich in saturated fats, which are notorious for contributing to raised blood cholesterol levels and therefore to the risk of heart disease. However, much of the saturated fat in cocoa butter is a particular fatty acid that the body immediately converts into an unsaturated one (stearic acid is converted to oleic acid). So chocolate is not thought to pose a risk to the heart. In fact, it may well be beneficial. Cocoa particles are a tremendously rich source of antioxidant phenolic compounds, which account for 8% of the weight of cocoa powder. The higher the cocoa solids content of a chocolate or candy, the higher its antioxidant content. Any added sugar, milk products, or cocoa butter simply dilute the cocoa solids and their phenolics. The dutching process also reduces the levels of desirable phenolics in cocoa powder, and the milk proteins in milk chocolate appear to bind to the same molecules and prevent us from absorbing them.

Caffeine and Theobromine Chocolate contains two related alkaloids, theobromine and caffeine, in the ratio of about 10 to 1. Theobromine is a weaker stimulant of the nervous system than caffeine is (p. 433); its main effect seems to be a diuretic one. (However it is quite toxic to dogs, who can suffer serious poisoning from chocolate candies.) A 1-oz /30 gm piece of unsweetened chocolate contains around 30 mg of caffeine, around a third the dose in a cup of coffee; sweetened and milk chocolates contain substantially less. Cocoa powder has around 20 mg caffeine per tablespoon/10 g.

Cravings for Chocolate Because many people, especially women, experience cravings for chocolate that border on the symptoms of addiction, it has been thought that chocolate might contain psychoactive chemicals. Chocolate does turn out to contain both “cannabinoid” chemicals — chemicals similar to the active ingredient in marijuana — as well as other molecules that cause brain cells to accumulate cannabinoid chemicals. But these are present in extremely small amounts that probably have no practical significance. Similarly, chocolate contains phenylethylamine, a naturally occurring body chemical that has amphetamine-like effects — but then so do sausages and other fermented foods. In fact there is good experimental evidence that chocolate does not contain any drug-like substances capable of inducing a true addiction. Psychologists have shown that chocolate cravings can be satisfied by imitations that have no real chocolate in them, while these cravings are not satisfied by capsules of genuine cocoa powder or chocolate that are swallowed without tasting. It appears to be the sensory experience of eating chocolate, no more and no less, that is powerfully appealing.