The History of Sugars and Confectionery

Before Sugar: Honey

Sugar: Beginnings in Asia

Early Confectionery in Southwest Asia

In Europe: A Spice and Medicine

Confectionery for Pleasure

A Pleasure for All

Sugar in Modern Times

The Nature of Sugars

Kinds of Sugar

The Complexities of Sweetness

Crystallization

Caramelization

Sugars and Health

Sugar Substitutes

Sugars and Syrups

Honey

Tree Syrups and Sugars: Maple, Birch, Palm

Table Sugar: Cane and Beet Sugars and Syrups

Corn Syrups, Glucose and Fructose Syrups, Malt Syrup

Sugar Candies and Confectionery

Setting the Sugar Concentration: Cooking the Syrup

Setting the Sugar Structure: Cooling and Crystallization

Kinds of Candies

Chewing Gum

Candy Storage and Spoilage

Chocolate

The History of Chocolate

Making Chocolate

The Special Qualities of Chocolate

The Kinds of Chocolate

Chocolate and Cocoa as Ingredients

Tempered Chocolate for Coating and Molding

Chocolate and Health

Ordinary sugar is an extraordinary food. Sugar is pure sensation, crystallized pleasure. All human beings share an innate liking for its sweetness, which we first experience in mother’s milk, and which is the taste of the energy that fuels all life. Thanks to this deep appeal, sugar and sugar-rich foods are now among the most popular and widely consumed of all foods. In centuries past, when sugar was rare and expensive, they were luxuries reserved for the wealthy and for the climax of the meal. Today sugar is cheap, and manufactured sweets have become everyday, casual pleasures, affordable and entertaining morsels. Some are soothing classics, cream and sugar cooked into rich brown caramels, or clear sugar tinted to look like a shard of stained glass. And others are provocative novelties with glaringly unnatural colors, whimsical shapes, hidden pockets of hissing gas, and burningly excessive doses of acidity or spice.

In the kitchen, sugar is a versatile ingredient. Because sweetness is one of a small handful of basic taste sensations, cooks add sugar to dishes of all kinds to fill out and balance their flavor. Sugar interferes usefully with the coagulation of proteins, and so tenderizes the gluten network of baked goods and the albumen network of custards and creams. If we heat sugar enough to break its molecules apart, it generates both appealing colors and an increasing complexity of flavor: no longer just sweetness, but acidity, bitterness, and a full, rich aroma. And sugar is a sculptural material. Provide it with some moisture and high heat, and we can coax from it a broad range of shapeable consistencies, creamy and chewy and brittle and rock hard.

The story of sugar is not all sweetness and light. Its appeal was a destructive force in the history of Africa and the Americas, whose peoples were enslaved to satisfy the European hunger for it. And today, by displacing more nourishing foods from our diet, sugar contributes indirectly to several modern diseases of affluence. Like most good things in life, it’s best enjoyed in moderation. And like that other good thing, fat, it’s easy to consume a lot of sugar in manufactured foods without realizing it.

Chocolate, the cooked, sculptable paste of a South American tree seed, has been married to sugar ever since its arrival in Europe nearly 500 years ago, and is in some respects sugar’s complement. Where sugar is a single molecule purified from complex plant fluids, chocolate is a mixture of hundreds of different molecules produced by fermenting and roasting a plain bland seed. It’s one of the most complex flavors we experience, and yet it lacks and is completed by basic, simple sweetness.

Gathering honey in prehistoric times. This rock painting, found in the Spider Cave at Valencia, Spain, dates back to about 8000 BCE and appears to show two people raiding a wild beehive. The leader (enlarged at right) may be carrying a basket for the honeycomb. Artificial hives and the domestication of bees are known from about 2500 BCE in Egypt. (Redrawn from H. Ransome, The Sacred Bee, 1937.)

The History of Sugars
and Confectionery

Before Sugar: Honey

After mother’s milk, the first significant source of sweetness in human experience must have been fruits. Some warm-climate fruits like the date can approach a sugar content of 60%, and even temperate fruits become very sweet when they dry out. But the most concentrated natural source of sweetness is honey, the stored food of certain species of bees, which reaches 80% sugars. It’s clear from a remarkable painting in the Spider Cave of Valencia that humans have gone out of their way to collect honey for at least 10,000 years. The “domestication” of bees probably goes back 4,000 years, judging by Egyptian hieroglyphs that show clay hives.

However our ancestors obtained it, honey came to represent pleasure and fulfillment to them, and is a prominent metaphor in some of the earliest literature we know. A love poem inscribed 4,000 years ago on a Sumerian clay tablet describes a bridegroom as “honeysweet,” the bride’s caress as “more savory than honey,” and their bedchamber as “honeyfilled.” In the Old Testament, the promised land is pictured several times as a land flowing with milk and honey, a metaphor of delightful plenty that is itself used figuratively in the Song of Songs, where another bridegroom chants, “Thy lips, O my spouse, drop as the honeycomb: honey and milk are under thy tongue…”

Honey remained an important ingredient in both the food and culture of classical Greece and Rome. The Greeks offered it in ceremonies to the dead and the gods, and priestesses of the goddesses Demeter, Artemis, and Rhea were called melissai: the Greek melissa, like the Hebrew deborah, means “bee.” The prestige of honey was due in part to its mysterious origins and to a belief that it was a little bit of heaven fallen to earth. The Roman natural historian Pliny speculated in entertaining detail on honey’s nature.

It was more than 1,000 years before the true roles of flower and bee in the creation of honey were uncovered (p. 663). In fact, honey making is the natural model for all human sugar production. We too take sweet juices from plants and separate the sugars from the water. Palm trees in South Asia, maple and birch trees in northern forests, agave plants and maize stalks in the Americas: all these have provided the sweet juices. But none of them has been as generous as sugarcane.

Sugar: Beginnings in Asia

Europe barely knew what we now consider ordinary table sugar until around 1100, and it was a luxury until 1700. Our first major source of sucrose was the sugar cane, Saccharum officinarum, a 20-foot-tall member of the grass family with an unusually high sucrose content — about 15% — in its fluids. Sugar cane originated in New Guinea in the South Pacific and was carried by prehistoric human migration into Asia. Sometime before 500 BCE, people in India developed the technology of making unrefined, “raw” sugar by pressing out the cane juice and boiling it down into a dark mass of syrup-coated crystals. By 350 BCE, Indian cooks were combining this dark gur with wheat, barley, and rice flours and with sesame seeds to make a variety of shaped confections, some of them fried. A couple of centuries later, Indian medical texts distinguished among a number of different syrups and sugars from cane, including crystals from which the dark coating had been washed. These were the first refined white sugars.

Early Confectionery in Southwest Asia

Around the 6th century CE, both the cane and sugar-making technology were carried westward from the delta of the Indus River to the head of the Persian Gulf and the delta of the Tigris and Euphrates rivers, where the Persians made sugar a prized ingredient in their cooking. One modern survival of this esteem is the sprinkling of large sugar crystals over a dish called “jeweled rice.” Islamic Arabs conquered Persia in the 7th century and took the cane to northern Africa, Syria, and eventually Spain and Sicily. Arab cooks combined sugar with almonds to make marzipan paste, cooked it down with sesame seeds and other ingredients to make chewy halvah, made great use of sugar in syrups aromatized with rose petals and orange blossoms, and were pioneers in confectionery and in sugar sculpture. There are records of a 10th-century feast in Egypt that was adorned with sugar models of trees, animals, and castles!

In Europe:
A Spice and Medicine

Western Europeans first encountered sugar during their Crusades to the Holy Land in the 11th century. Shortly thereafter Venice became the hub of the sugar trade from Arab countries to the West, and the first large shipment to England that we know of came in 1319. At first, Europeans treated sugar the way they treated pepper, ginger, and other exotic imports, as a flavoring and a medicine. In medieval Europe, sugar was used in two general sorts of preparations: preserved fruits and flowers, and small medicinal morsels. Sweets, or candy, began not as little entertaining treats but as “confections” (from the Latin conficere, “to put together,” “to prepare”) composed by the apothecaries, or druggists, to balance the body’s principles. Sugar served several medicinal purposes. Its sweetness covered the bitterness of some drugs and made all preparations more pleasant. Its meltability and stickiness made it a good vehicle for mixing and carrying other ingredients. The solidity of a fused mass of sugar meant that it could release its medicine slowly and gradually. And its own supposed effect on the body — encouraging both heat and moisture — was thought to balance the effects of other foods and enhance the digestive process. A number of soothing medicinal sweets remain popular to this day, including lozenges, pastilles, and comfits.

Confectionery for Pleasure

It’s thought that the first nonmedical confection in Europe may have been made around 1200 by a French druggist who coated almonds with sugar. Medieval recipes from the French and English courts call for sugar to be added to fish and fowl sauces, to ham, and to various fruit and cream-egg desserts. Chaucer’s Tale of Sir Topas, a 14th-century parody of the chivalric romance, included sugar in a list of “royal spicery,” along with gingerbread, licorice, and cumin. By the 15th century, wealthy Europeans had come to appreciate the purely pleasurable virtues of sugar and its ability to complement the flavors of many foods. The Vatican librarian Platina wrote around 1475 that sugar was being produced in Crete and Sicily as well as India and Arabia, and added,

Advances in Confectionery In the 15th and 16th centuries, confectionery became more of an art, done with greater sophistication and intended more and more to delight the eye. Molten sugar was now spun into delicate threads and pulled to develop a satiny sheen, and confectioners began to develop ways of determining the different states of a sugar syrup and their appropriateness to different preparations. By the 17th century, court confectioners were making whole table settings and massive decorations out of sugar, hard sugar candies had become common, and cooks had developed systems for marking the syrup concentrations suitable for different confections — ancestors of today’s thread-ball-crack scale (see box, p. 651).

A Pleasure for All

Sugar became more widely available in the 18th century, when whole cookbooks were devoted to confectionery. England developed an especially strong sugar habit, and consumed large amounts in the tea and jams that fueled the working class. The per capita consumption rose from 4 pounds/2 kg a year in 1700 to 12 pounds/5 kg in 1780. By contrast, the French limited their use of sugar mainly to preserves and to desserts. In the 19th century, the growing production of sugar from beets, and the development of machines that automated the cooking, manipulation, and shaping of sugar preparations, brought inexpensive candies for all and encouraged an inventiveness that continues to this day. It’s in the 19th century that familiar modern candies and chocolates were invented, and the control of crystallization was refined. Taffy or toffee, from the Creole for a mixture of sugar and molasses, and nougat, from the vulgar Latin for “nut cake,” entered the language early in the century; fondant, from the French for “melting,” the basic material of fudge and all semisoft or creamy centers, was developed around 1850. Most candy today is a variation of some kind on bonbons, taffy, and fondant.

The Rise of the Sugar Industry The 18th-century explosion in European sugar consumption was made possible by colonial rule in the West Indies and the enslavement of millions of Africans. Columbus carried the cane to Hispaniola (now Haiti and the Dominican Republic) on his second voyage in 1493. By about 1550, the Spanish and Portuguese had occupied many Caribbean islands and the coasts of western Africa, Brazil, Mexico, and were producing sugar in significant quantities; English, French, and Dutch colonists followed in the next century. By 1700, some 10,000 Africans were being traded via the Portuguese colony São Tomé to the Americas every year. The sugar industry was not the only force behind the great expansion of slavery, but it probably was the major force and helped ease its introduction into the southern American colonies and the cotton plantations. According to one estimate, fully two-thirds of the 20 million Africans enslaved in the Americas worked on sugar plantations. The intricate trade in sugar, slaves, rum, and manufactured goods made major ports out of the hitherto minor cities of Bristol and Liverpool in England, and Newport, Rhode Island. And the huge fortunes made by plantation owners helped finance the opening stages of the Industrial Revolution.

In the 18th century, just when it seemed at its strongest, the West Indian sugar industry began a rapid decline. The horrors of slavery gave rise to abolition movements, especially in Britain. Slaves staged revolts, and received some support from the very countries that had carried them to the plantations. One by one, through the mid-19th century, European countries outlawed slavery in the colonies.

The Development of Beet Sugar The severest blow to West Indian sugar was the development of an alternative to the sugar cane that could grow in northern climates. In 1747, a Prussian chemist, Andreas Marggraf, showed that by using brandy to extract the juice of the white beet (Beta vulgaris, var. altissima), a common European vegetable, he could isolate crystals that were identical to those purified from sugar cane, and in comparable quantities. Marggraf foresaw a kind of cottage industry by which individual farmers could satisfy their own needs for sugar, but this never came about, and many years passed before the idea escaped the laboratory. In 1811, the Emperor Napoleon officially set the goal of freeing France from dependence on the English colonies for various commodities, and in 1812 personally awarded a medal to Benjamin Delessert, who had developed a working sugar-beet factory. In the next year, 300 such factories sprang up. A treaty resuming trade between France and England was signed in 1814, making West Indian sugar available once again, and the fledgling industry crashed as suddenly as it had begun. But it rose again in the 1840s and has flourished ever since.

Sugar in Modern Times

At present, beet sugar accounts for about 30% of the sucrose produced in the world. Russia, Germany, and the United States are the major beet growers, with California, Colorado, and Utah the leading states. The Caribbean is now a minor source of cane sugar, its role having been assumed by India and Brazil. Florida, Hawaii, Louisiana, and Texas also produce sugar cane. Spurred by the demand of an increasingly populous and affluent West, world sugar production increased sevenfold between 1900 and 1964, a rate matched by no other major crop in history. And thanks to the development of methods for making sweeteners from corn, an even less expensive source, sugar has never been cheaper or more abundant in our diet. This is not necessarily good for our long-term health (p. 657), and one of the major developments in 20th-century food manufacturing has been the development of ingredients that mimic the flavor and physical characteristics of sugar without having adverse effects on body weight and the regulation of blood sugar (p. 659).

The Nature of Sugars

Ordinary sugar is one member of a group of many chemicals, all of which are given the general name sugars. All sugars are made from just three kinds of atoms, carbon, hydrogen, and oxygen, with the carbon atoms providing a kind of backbone to which the other atoms are attached. Some sugars are simple molecules, while others are made from two or more simple sugars joined together. Glucose and fructose are simple monosaccharides, while table sugar, or sucrose, is a disaccharide made up of one glucose and one fructose joined together.

Living things put the sugars to two primary uses. The first is the storage of chemical energy. All life depends on sugars for the energy that fuels the activity of cells. This is why we have taste receptors that register the presence of sugars, and why our brain attaches pleasure to that sensation: sweetness is the sign of a food that can help supply our need for calories. The second major role for sugars is to provide building blocks for physical structures, especially in plants. The cellulose, hemicellulose, and pectin that give bulk and strength to plant cell walls are long chains of various sugars. The simple physical bulk of sugar is also useful to the cook, who can construct from it a variety of interesting textures.

One chemical characteristic of sugars is especially important in the kitchen. Sugars have a strong affinity for water, so they readily dissolve in water, and form temporary but strong bonds to water molecules in their vicinity. Sugars therefore retain moisture in baked goods, keep frozen desserts from solidifying into a solid block of ice, form a sticky matrix that holds food particles together in such things as marzipan and granola bars, maintain a moist, glossy appearance in glazes, and help preserve fruits by drawing moisture out of spoilage microbes and preventing their growth.

Kinds of Sugar

The cook works with just a handful of the many different sugars in nature. All of them are sweet, but each has its distinctive qualities.

Glucose Glucose, also called dextrose, is a simple sugar, and the most common sugar from which living cells directly extract chemical energy. Glucose is found in many fruits and in honey, but always in a mixture with other sugars. It’s the building block from which starch chains are constructed. Cooks encounter it most often as the sweet substance in corn syrup, which is made by breaking starch down into individual glucose molecules and small glucose chains (p. 677). A chain of two glucoses is called maltose. Compared to table sugar, or sucrose, glucose is less sweet, less soluble in water, and produces a thinner solution. It melts and begins to caramelize at around 300ºF/150ºC.

Fructose Fructose, also called levulose, has exactly the same chemical formula as glucose, but the atoms are arranged in a different structure. Like glucose, fructose is found in fruits and honey, and certain corn syrups are treated with enzymes to convert their glucose into fructose. It’s also sold in pure crystalline form. Fructose is the sweetest of the common sugars, the most soluble in water (4 parts will dissolve in 1 part room-temperature water), and absorbs and retains water most effectively. Our bodies metabolize fructose more slowly than glucose and sucrose, so it causes a slower rise in blood glucose levels, a quality that makes it preferable to other sugars for diabetics. Fructose melts and begins to caramelize at a much lower temperature than the other sugars do, just above the boiling point of water at 220ºF/105ºC.

The fructose molecule exists in several different shapes when dissolved in water, and the different shapes have different effects on our sweet receptors. The sweetest shape, a six-corner ring, predominates in cold, somewhat acid solutions; in warm or hot conditions, this shape shifts to less sweet five-corner rings. The apparent sweetness of fructose is cut nearly in half at 140ºF/60ºC. Neither glucose nor sucrose changes so drastically. Fructose is thus a useful substitute for table sugar in cold drinks, where it can provide the same sweetness with half the concentration and a calorie savings approaching 50%. In hot coffee, however, its sweetness drops to the level of table sugar.

Sucrose Sucrose is the scientific name for table sugar. It is a composite molecule made of one molecule each of glucose and fructose. Green plants produce sucrose in the process of photosynthesis, and we extract it from the stalks of sugar cane and the storage stems of sugar beets. Of all the common sugars, it has the most useful combination of properties. It is the second sweetest, after fructose, but is alone in having a pleasant taste even at the very high concentrations found in candies and preserves; other sugars can seem harsh. Sucrose is also the second most soluble sugar — two parts can dissolve in one part of room-temperature water — and it produces the greatest viscosity, or thickness, in a water solution. Sucrose begins to melt around 320ºF/160ºC, and caramelizes at around 340ºF/170ºC.

When a solution of sucrose is heated in the presence of some acid, it breaks apart into its two subsugars. Certain enzymes will do the same thing. Breaking sucrose into glucose and fructose is often referred to as inversion, and the resulting mixture is called invert sugar or invert syrup. (“Inversion” refers to a difference in optical properties between sucrose and a mixture of its components parts.) Invert syrups are about 75% glucose and fructose, 25% sucrose. Invert sugar only exists as a syrup, since the fructose component won’t fully crystallize in the presence of glucose and sucrose. Sucrose inversion and invert sugars are useful in candy making because they help limit the extent of sucrose crystallization (p. 685).

Common sugars. Carbon atoms are shown as dots. Glucose and fructose have the same chemical formula, C₆H₁₂O₆, but different chemical structures, and different degrees of sweetness. A given concentration of fructose tastes much sweeter than the same concentration of glucose. Table sugar, or sucrose, is a combination of glucose and fructose (a molecule of water is released when the two sugars bond to make sucrose).

Lactose Lactose is the sugar found in milk. It is a composite of two simple sugars, glucose and galactose. Cooks seldom encounter it in pure form. Because it’s much less sweet than table sugar, manufacturers use it much as they do the sugar alcohols (p. 662), more for its physical bulk than for its sweetness.

The Complexities
of Sweetness

There’s more to the sweetness of sugars than the sensation of sweetness pure and simple. Sweetness helps mask or balance both sourness and bitterness from other ingredients. And flavor chemists have shown that it has a strong enhancing effect on our perception of food aromas, perhaps by signaling the brain that the food is a good energy source and therefore deserves special attention.

Different sugars give different impressions of sweetness. Sucrose takes some time to be detected on the tongue, and its sweetness lingers. By comparison, the sweetness of fructose registers quickly and strongly, but it also fades quickly. And corn syrup is slow to taste sweet, peaks at about half the intensity of sucrose, and lingers even longer than sucrose. The quick action of fructose is said to enhance certain other flavors in foods, especially fruitiness, tartness, and spiciness, by allowing us to perceive them clearly without the masking effect of residual sweetness.

Crystallization

Sugars are wonderfully robust materials! Unlike proteins that easily denature and coagulate, unlike fats that are damaged by air and heat and go rancid, unlike starch chains that break apart into smaller chains of glucose molecules, sugars themselves are small and stable molecules. They mix easily with water, tolerate the heat of boiling, and when sufficiently concentrated in water, they readily bond to each other and collect themselves into pure, solid masses, or crystals. This tendency to form crystals is the means by which we obtain pure sugar from plant juices, and it’s the way that we make many kinds of candies. Sugar crystallization is described in detail on p. 682.

Caramelization

Caramelization is the name given to the chemical reactions that occur when any sugar is heated to the point that its molecules begin to break apart. This destruction triggers a remarkable cascade of chemical creation. From a single kind of molecule in the form of colorless, odorless, simply sweet crystals, the cook generates hundreds of new and different compounds, some of them small fragments that are sour or bitter, or intensely aromatic, others large aggregates with no flavor but a deep brown color. The more the sugar is cooked, the less sugar and sweetness remain, and the darker and more bitter it gets.

Though caramel is most often made with table sugar, its sucrose molecules actually break apart into their glucose and fructose components before they begin to fragment and recombine into new molecules. Glucose and fructose are “reducing sugars,” meaning that they have reactive atoms that perform the opposite of oxidation (they donate electrons to other molecules). A sucrose molecule is made from one glucose and one fructose joined by their reducing atoms, so sucrose has no reducing atoms free to react with other molecules, and is therefore less reactive than glucose and fructose. This is why sucrose requires a higher temperature for caramelization (340ºF/170ºC) than glucose (300ºF/150ºC) and especially fructose (220ºF/105ºC).

The flavors of caramelization. Heat transforms table sugar, a sweet, odorless, single kind of molecule, into hundreds of different molecules that generate a complex flavor and rich brown color. A few aromatic examples (clockwise from top left) : alcohol, sherry-like acetaldehyde, vinegary acetic acid, buttery diacetyl, fruity ethyl acetate, nutty furan, solvent-like benzene, and toasty maltol.

Making Caramel The usual technique for making caramel is to mix table sugar with some water, then heat until the water has boiled off and the molten sugar colors. Why add water if the first thing you do is boil it off? Water makes it possible to cook the sugar over high heat from the very beginning without the danger of burning it. In addition, the presence of water prolongs the period during which the syrup is cooked, gives these reactions more time to proceed, and develops a stronger flavor than heating the sugar on its own very quickly. And water enhances the conversion of sucrose into its glucose and fructose components. Cooking the syrup in the microwave oven has been found to produce a somewhat different spectrum of flavors than ordinary stovetop cooking.

Once caramelization and color and flavor generation begin, the overall set of reactions actually gives off heat, and can run away and burn the sugar if it’s not carefully controlled. It’s helpful to have a bowl of cold water ready to cool the pan down as soon as the caramel is done. Excessive caramelization turns the syrup very dark, bitter, and viscous or even solid.

The Flavor of Caramelized Sugar The aroma of a simple caramelized sugar has several different notes, among them buttery and milky (from diacetyl), fruity (esters and lactones), flowery, sweet, rum-like, and roasted. As the reactions proceed, the taste of the mixture becomes less sweet as more of the original sugar is destroyed, with more pronounced acidity and eventually bitterness and an irritating, burning sensation. Some of the chemical products in caramel are effective antioxidants and can help protect food flavors from damage during storage.

When sugars are cooked with ingredients that include proteins or amino acids — milk or cream, for example — then in addition to true caramelization, some of the sugars participate with the proteins and amino acids in the Maillard browning reactions (p. 778), which produce a larger range of compounds and a richer aroma.

Sugars and Health

“Empty Calories” In one sense, sugars are highly nourishing. Pure sugars are pure energy. After fats and oils, they’re the most concentrated source of calories we have. The problem is that most people in the developed world consume more energy than they need to fuel their activity, and less than they need of hundreds of other nutrients and plant substances that contribute to long-term health (p. 253). To the extent that sugar-rich foods displace more broadly nourishing foods from our diet, they are detrimental to human health, a source of calories “empty” of any other nutritional value, and a major contributor to the modern epidemic of obesity and associated health problems, including diabetes (p. 659).

People in the developed world, particularly in the United States, consume large amounts of refined sugars. Adults in the United States get about 20% of their calories from refined sugars, children between 20% and 40%. Most of this sugar intake comes not from candies and confections, but from soft drinks. Significant amounts of sugar also find their way into most processed foods, including many savory sauces, dressings, meats, and baked goods. The total sugar content in processed foods is often unclear from the ingredients list, where different sugars can be listed separately as sucrose, dextrose, levulose, fructose, corn syrup, high-fructose corn syrup, etc.

Sugars and Tooth Decay It has been common knowledge for thousands of years that sweet foods encourage tooth decay. In the Greek book of Problems attributed to Aristotle, the question is asked, “Why do figs, which are soft and sweet, destroy the teeth?” Nearly 2,000 years later, as sugar cane was being established in the West Indies, a German visitor to the English court named Paul Hentzner described Queen Elizabeth I as she appeared in 1598:

We now know that certain kinds of Streptococcus bacteria colonize the mouth and cling to undisturbed surfaces, where they live on food residues, converting sugars into sticky “plaque” carbohydrates that anchor and protect them, and into defensive acids that eat away at tooth enamel and so cause decay. Clearly, the more food there is for the bacteria, the more active they will be, and hard sugar candies that slowly dissolve in the mouth provide a feast for them. But pure sugar is not the only culprit in tooth decay. Starchy foods like bread, cereals, pasta, and potato chips are also harmful because they stick to the teeth and then are broken down into sugars by enzymes in the saliva. A few other foods, notably chocolate, cocoa, and licorice extract among candy ingredients, as well as coffee, tea, beer, and some cheeses, actually inhibit decay-causing bacteria. There’s evidence that phenolic compounds interfere with the adhesion of bacteria to the teeth. The sugar alcohols in low-calorie candies (p. 662) are generally not metabolized by bacteria in the mouth and don’t contribute to tooth decay.

Food Sugars and Blood Sugar: The Problem of Diabetes Some foods rich in sugars can contribute to the disruption of the body’s system for controlling its own sugar levels. Glucose is the body’s primary form of chemical energy, so it’s distributed to all cells via the blood. On the other hand, glucose is a reactive molecule, and excess quantities can damage the circulatory system, eyes, kidneys, and nervous system. So the body tightly regulates blood glucose levels, and does so with the hormone insulin. Diabetes is a disease in which the insulin system is unable to control blood glucose adequately. And a high intake of some food sugars overloads the blood with glucose and puts stress on the insulin system. This is dangerous for people who suffer from diabetes. The foods that raise blood glucose levels the most are foods rich in glucose itself, including such starchy foods as potatoes and rice that our enzymes digest into glucose. Table sugar, a combination of glucose and fructose, has a somewhat smaller effect, and fructose itself has a much smaller effect, since it must be metabolized in the liver before the body can use it for energy. One valuable property of many sugar substitutes is that they do not raise blood sugar levels.

Sugar Substitutes

Sugars combine several useful qualities in one ingredient: energy, sweetness, substance, moisture binding, and the ability to caramelize. The problem with this versatility is that each quality comes with the others. And sometimes we want just one or two alone: the pleasure of sweetness without the calories or stress on the body’s system for regulating blood sugar levels, for example, or the substance without the sweetness, or substance and sweetness without the tendency to brown when cooked. Manufacturers have therefore developed ingredients that offer some but not all of the properties of sugars. Many of these ingredients were originally discovered in plants; a few are entirely artificial. Inventive cooks are now experimenting with some to make candy-like savory foods and other novelties.

There are two main kinds of sugar substitutes. The first includes various carbohydrates that provide bulk without being as digestible as the sugars. They therefore don’t raise blood sugar levels as quickly, and supply fewer calories. The second is high-intensity sweeteners: molecules that provide the sensation of sweetness without supplying many calories, usually because they are hundreds or thousands of times sweeter than sugar, and are used in tiny quantities. Low-and no-calorie sweets are made by combining these two kinds of ingredients, whose qualities are summarized in the chart on pp. 660–661.

Bulking Ingredients: Sugar Alcohols The most common ingredients that provide sugar-like bulk are the sugar alcohols, or polyols — chemicals whose names end in -itol — which are essentially sugars with one corner of their molecule modified (for example, sorbitol is derived in this way from glucose). Small amounts of some sugar alcohols — sorbitol, mannitol — are found in many fruits and plant parts. Because the human body is designed to make use of sugars, not sugar alcohols, we absorb only a fraction of these molecules from food, and use that fraction inefficiently: so they cause only a slow rise in blood insulin levels. The rest are metabolized by the microbes in our intestines, and we obtain their energy indirectly. All told, sugar alcohols provide 50–75% of the caloric value of sugar.

Sugar alcohols don’t have the chemical structure (aldehyde group) that initiates the browning reactions with each other and with amino acids, so they have the sometimes useful property of being resistant to discoloration and flavor changes when heated to make confections.

Intensive Sweeteners Though most of the intensive sweeteners that we consume today were synthesized in industrial laboratories, a number of them occur in nature and have been enjoyed for centuries. Glycyrrhizin or glycyrrhizic acid, a compound found in licorice root, is 50–100 times sweeter than sucrose, and is the reason that licorice was first made into a sweet by extracting the root in hot water, then boiling down the extract. The sweetness of the extract builds slowly in the mouth and lingers. And the leaves of a South American plant commonly known as stevia, Stevia rebaudiana, have been used for centuries in its homeland to sweeten maté tea. Its active ingredient, stevioside, is available in a purified powdered form. Neither it nor the plant has been approved by the U.S. FDA as a food additive, so they’re sold as dietary supplements.

Intensive sweeteners often have some flavor qualities that make them imperfect replacements for table sugar. For example, saccharin has a metallic aftertaste and can seem bitter; stevioside has a woody after-taste. Many are slower than table sugar to trigger the sensation of sweetness, and their taste persists longer after swallowing. The relative sweetness of these sweeteners actually goes down as their individual concentration goes up, while combining them produces a synergistic effect. So manufacturers often use two or more to minimize their odd qualities and maximize their taste intensity.

Aspartame, a synthetic combination of two amino acids, is the most widely used noncaloric sweetener. It is 180–200 times sweeter than table sugar, so that though it carries the same number of calories in a given weight, much smaller amounts are needed. Aspartame’s disadvantage is that it is broken down by heat and by acidity and therefore can’t be used in cooked preparations.

Sweetness Inhibitors Not only are there artificial sweeteners: there are also substances that block us from experiencing the sweetness of sugars. These taste inhibitors are useful for reducing the sweetness of a preparation whose texture depends on a high sugar concentration. Lactisole (tradename Cypha) is a phenolic compound found in small quantities in roasted coffee, patented as a flavor modifier in 1985, and used in confectionery and snacks. In very small amounts it reduces the apparent sweetness of sugar by two-thirds.

Sugars and Syrups