Sugar has a complicated mystique. It’s a superb chemical feedstock that can be used in gasoline substitutes, drug delivery and plastics. It also makes for a fine food ingredient.
“Sugar” is a chemical designation, the discrete molecular units that make up carbohydrates. Many sugars have the formula C6H12O6 but they are joined at different parts of a generally hexagonal ring structure. They may be oriented in more than one plane. Different connections yield different types of sugars.
Sugar can be derived from virtually any plant source, but most sugars come from cane, beets and sorghum.
|Turbinado is the first pressing of cane juice that is crystallized and sometimes steam-cleaned to retain traces of the original molasses.
Carbohydrates that contain only one sugar unit (monosaccharides) or two sugar units (disaccharides) are referred to as simple sugars. Simple sugars are sweet in taste and are broken down quickly in the body. Two of the most common monosaccharides are glucose and fructose.
Glucose is the primary form of sugar stored in the human body. Fructose is the main sugar found in most fruits. Both glucose and fructose have the C6H12O6 chemical formula but have slightly different structures.
Disaccharides have two sugars bonded together. For example, common table sugar is sucrose, a disaccharide that consists of a glucose unit bonded to a fructose unit. The caloric content of sucrose – 4 calories per gram – is the standard against which all sugars and artificial sweeteners are measured.
Connect enough sugar molecules and you get starches. These complex carbohydrates, which are long chains of glucose units, are broken down by enzymes. Unless the sugar units are arranged so human enzymes are not effective in breaking down the chain, the caloric loads of sugars and starches are the same.
Except for sugar alcohols. Sugar alcohols, also know as polyols, are much less sweet than sugars, contribute fewer calories (anywhere from one third to one-half fewer) and are converted to glucose more slowly. This makes them good bulking agents. Common sugar alcohols are mannitol, sorbitol, xylitol, lactitol, isomalt, maltitol and hydrogenated starch hydrolysates.
Enzymes are used to affect the structure of sugars. When some of those enzymes are not found in the human body, the sugar is indigestible or only slowly digestible. One example is trehalose, which is only partly digestible; so are some of the D-sugars.
Depending on the way the sugar units are oriented, the sugar can be digested easily, slowly or not at all. And the uses and manufacturing of the products can be highly technical or as uncomplicated as adding sweetness to coffee. Depending upon the source and the processing care, the end results even can be certified as organic.
New: Organic sugars
A real holdup to manufacturing many organic products has been sugar. The chemical processing needed to transform sugars into pure, white crystals was outside the definition of “organic” or “natural.” But no more.
Domino, Florida Crystals and C&H Sugar (now owned by the same firm, Domino, www.dominospecialtyingredients.com), have found a way to use a single crystallization step, without added chemicals, to process organically grown sugar cane which is pressed the day it’s cut. It meets the requirements of the USDA’s National Organic Program and is certified organic by Quality Assurance International. It looks like regular sucrose.
|Only recent advances in processing have enabled white, crystalline sucrose to be made in a process that satisfies organic standards.
Along with organic sucrose, there are other forms of natural or organic sucrose offered with some slight alterations. Turbinado (sometimes spelled turbanado) has been around for centuries. It is a first pressing of cane juice that is crystallized and sometimes steam-cleaned to retain traces of the original molasses. Color in different products ranges from amber to dark brown, and it has a more “natural” image and has been described as healthier than refined sucrose. It contains traces of minerals, including calcium, phosphorus, magnesium, potassium and iron.
Popular in the United Kingdom is Barbados sugar, a very dark brown sugar with a strong molasses flavor. The crystals are coarse and sticky. Another variation is demerara sugar, also popular in England, which is light brown with big golden crystals. The crystals are a little sticky, and the product generally is used in hot beverages and on hot cereals.
Muscovado is a very dark brown sugar with a strong molasses flavor, originally crystallized from the first boiling in the mill. The crystals are larger than brown sugar but not as large as turbinado or demerara sugar crystals and very sticky.
Last fall, Wholesome Sweeteners (www.wholesomesweeteners.com) of Sugarland, Texas, introduced its entry into the organic arena: Sweet & Fair. In addition to being organic, this sugar is produced under international “fair trade” standards, which guarantees fair prices to farmers, particularly in developing nations, and also supports a safe workplace (usually precluding the use of pesticides), the right to unionize and the prohibition of child and slave labor.
“We have always been proud of our record of sourcing the finest quality cane sugars from the best environmentally and socially responsible producers,” said CEO Nigel Willerton. “The decision to certify [as fair trade-sourced] our line of organic sugars comes from our company’s commitment to make a difference in our community and the world with every spoonful of sugar.” The firm believes that elimination of pesticides from the cane fields, and growing in a sustainable way, will allow the premium. Wholesome Sweeteners is a division of The Billington Group, a specialty foods company from the United Kingdom.
Hain Pure Foods, a Boulder, Colo., division of Hain Celestial Group, has introduced two organic breath mint products (mint and cinnamon) that are certified organic by Oregon Tilth and sweetened with organically grown cane juice. The firm also offers a full line of organic sugars, including turbinado, organic sugar, organic brown sugar and organic powdered sugar.
A major user of organic sugar is food processing giant H.J. Heinz Co. The Pittsburgh company introduced Heinz Organic Ketchup in mid-2002. Casey Keller, managing director for ketchup, noted at the time, “The organic condiments category is growing rapidly because consumers today want more choices that fit their lifestyles. We believe the time is now right to bring Heinz to this fast-growing segment of consumers.” According to a spokesperson, sales continue to be good.
The functions of sugar
A major problem with removing sugar from foods is sugar provides function as well as flavor. Sugar acts as a tenderizer in baked foods and custards; keeps the osmotic pressure high to prevent spoilage in jams, jellies, salad dressings and condiments; delays discoloration on the surface of frozen fruits; and crystallizes candies and frostings in specific ways to make particular textures.
Sugar is used to stabilize foams, trap air into batters and turn crusts a crispy brown. Sucrose, having a reducing end, triggers the Maillard reaction in dextrose in combination with protein and moisture. Using a sugar with fewer reducing ends, such as lactose or maltose, produces a paler crust in baked goods. Lactose and maltose are lower in sweetening power and are often used either to prevent the Maillard reaction or to reduce sweetness.
A popular use of sugars is to form a “glass” or glaze that encloses flavoring material, protecting it from oxidation. Dextrose, sucrose and maltose have been used for this purpose, and the special characteristics of the sugars provide some different effects. High-maltose syrups have been used for a number of years to make lollipops that don’t drip.
|Not too sweet: Domino’s new Envision product adds sugar’s texture and osmotic pressure conditions to foods such as salad dressings without imparting a sweet taste.
Sugar molecules come in a variety of sizes, and as they get larger (more glucose units in the string) they tend to become less sweet. But they may have interesting properties that deserve your attention. Maltodextrins that have about 14 to 20 glucose units (degree of polymerization) have been found to carry calcium into the gut where it is taken up more easily by the body.
Fructooligosaccharides of certain types appear to have this property as well. One such product from Orafti, called Beneo Synergy1, combines oligofructose and inulin, derived from chicory root. Oligofructose and inulin are natural ingredients that occur in most plants and vegetables. Chemically, the product is a glucose molecule bonded to multiple fructose molecules. The orientation of the molecules is such that enzymes in the normal human system cannot break the molecules apart, so many of them are not digested (so they don’t add calories). Because of this, they are often regarded as fiber.
Short-chain fructooligosaccharides are selectively fermented by the intestinal flora, so they can carry calcium to the lower intestine, where it is assimilated. According to Orafti, Synergy1 helps the body absorb more essential nutrients, such as calcium, from the diet.
Other sugar compounds such as branched maltodextrins, made by a combination of enzymes, are disclosed in patents assigned to Roquette Freres as a useful ingredient for improving the assimilation of calcium and magnesium in enteral formulas. The branched maltodextrins have a defined ratio of branching that is not digested by humans.
Cargill (through its Cerestar subsidiary) has opened a U.S. plant for the manufacture of polyols, which are being used in growing amounts, according to Per Ole Jensen, global business director of polyols. A new product called Maltidex HP (high purity) liquid maltitol, is a valuable replacement for crystalline maltitol, particularly in coated, sugar-free chewing gums, where it adds convenience, provides cost and labor savings and reduces bag waste. The product is 98 percent pure maltitol and can replace sucrose pound for pound.
Cargill has been active in designing new sweetening systems using polyols, sugars and high-intensity sweeteners to match the flavor and texture of full-fat, full-sugar formulas with fewer calories, says Kathy Fortmann, product manager for polyols and dextrose for Cargill Sweetness Solutions.
Not necessarily sweet
One big formulation quandary is gaining the functional properties of sugar in products that are not supposed to taste sweet. For this reason, corn millers have developed a number of low sweetness products, called maltodextrins. But these products, while very useful in some applications, are not crystalline enough for some uses and can be mildly sticky.
Now Domino has provided a sugar — sucrose crystals — that aren’t sweet. The product, called Envision, is co-crystallized sugar with a flavor modifier that prevents the sweetness receptors in the mouth from registering sweetness. The form of this sugar product is microsized crystals, formed of about 97 percent sucrose plus a bit of a sweetness modifier, blended with a little (3 percent) maltodextrin to aid the crystallization process.
Envision’s crystals are not hygroscopic, and they are instantly soluble. It’s designed to be a texture modifier, and the suggestion is that it can replace fat. It’s recommended for use in candy bars, confections in general, and in baked foods.
Another version, Super Envision, with 8-10 times as much sweetness modifier, is recommended for use in cheeses and meats. The ingredient statement includes “artificial flavor,” which is the way the sweetness modifier is labeled.
These products are useful in formulating meat, cheese and salad dressings that require the fat replacing, texture-enhancing qualities of sugar but taste “wrong” when sweetness is added, says David Poust, sales manager for these new Domino products.
About the Author
Frances Katz was vice president of research for American Maize Products, a past editor of Food Processing and was director of publications for the Institute of Food Technologists.
NOTE TO PLANT OPS
Using different sugars can require the plant to take careful care about processing plus ambient temperatures and humidity. Different sugars (dextrose, sucrose, maltose, etc.) may look similar, but they caramelize (brown) at different temperatures. In high humidity areas, they may become sticky at different rates.
Sugars should be kept in original packaging for as long as possible before they are added to other food products to protect them against stickiness. This also prevents them from picking up enough moisture to change the final product's moisture content. This is particularly important when using sugars in intermediate moisture products, when the addition of a fraction of a percent of moisture can affect shelf life.
MORE ON THE WEB
Type the word “sugar” into the search engine at www.FoodProcessing.com and you get 246 results: 188 articles, 25 news stories, 14 products, one whitepaper and 18 other items. Search under “sweetener” and you get 103 more hits. For all your web research needs, start your search at www.FoodProcessing.com.
The website www.scientificpsychic.com/fitness/carbohydrates.html offers lots of material further describing the sugars in this article.