Today, there are more sugar substitutes than at any time in our history. The driving force behind this growth is a combination of the epidemics of obesity and type 2 diabetes, the attempt to lower calories overall and what amounts to a relentless war on sugar.
This is not likely to change in the near future, as the obesity and diabetes issues show no signs of abating. At the same time, it is fruitless to lay the entire blame on sugar; it is but a single factor in a complex scenario.
The increase in daily per-capita sugar consumption over the past 40 years -- the period of rapid growth in obesity and diabetes -- is dwarfed by the increase in added fats and oils and the increase in refined flour and cereal products, according to the USDA food availability data (adjusted for loss). This also is roughly the same period in which average daily caloric consumption rose by almost 500 calories, while physical activity tumbled. Yet, due to some high-profile criticism, sugar is still perceived as Public Enemy No. 1 (especially high-fructose corn syrup, a sugar virtually chemically identical to sucrose, a.k.a. table sugar).
Another related trend is the interest in more natural sugar substitutes, including those derived from sugar molecules (both mono- and disaccharides). These are a step closer to natural sweeteners than those of purely synthetic derivation, such as saccharin (benzoic sulfilimine) and cyclamates (sodium or calcium salt of cyclamic acid), or derived from non-carbohydrate sources, for example aspartame. (Aspartame is a combination of two amino acids, aspartic acid and phenylalanine.)
It's worth revisiting sugar substitutes in light of the explosive success of monk fruit and stevia, extracts from a tropical fruit and a sweet-tasting leaf, respectively. All the different sugar-like substances display different physiological properties. As their use in healthful foods and beverages continues growing, processors are fine-tuning their application to create products that mimic their sugared versions better than ever.
Marketed under the name Palitinose (that trademark owned by Beneo), isomaltulose is a naturally occurring structural isomer (same basic chemical formula but different shape) of sucrose. It also has the same calorie value as sucrose, but a lower glycemic response, stimulating insulin at a slower rate than sucrose. It is believed to increase fatty acid oxidation in muscles and provide a more steady supply of glucose for the brain.
A 2012 study, demonstrated that, when given to persons with type 1 diabetics, isomaltulose provided more energy for running than did pure dextrose (glucose). When given as a substitute for sucrose, however, a 2013 study showed that there is no greater glycemic control provided to type 2 diabetics. It is also noncariogenic (does not promote tooth decay). Typically provided in the form of a white powder, it can be used as you would sugar. It is easily dispersed, does not clump and has enjoyed GRAS status since 2006.
Weighing in at half the calories of sugar (2 kcal/g), isomalt -- derived from beet -- is one of several sugar alcohols that serve as sugar substitutes. As such, it may potentially cause gastric distress if consumed in large quantities (50g per day for adults and 25g for children) because the body treats it more as a dietary fiber than a simple sugar.
Structurally, it's a type of "double disaccharide." A disaccharide is two linked single sugar molecules. (For example, sucrose is composed of glucose linked to fructose.) Isomalt is a mixture of glucose linked to sorbitol plus glucose linked to mannitol.
Isomalt has a very low impact on blood glucose and, as with isomaltulose, it won't promote tooth decay. Often, it is used in combination with a high-intensity sweetener that benefits from the positive physical properties of isomalt (moisture holding, minimal cooling effect, slower crystallization than sucrose).
Erythritol, with 60-70 percent the sweetening power of sucrose, is a naturally occurring sugar alcohol found in plants, seaweeds, fungi and a number of common fruits, such as melons, grapes and pears. It also is found in fermented foods (soy sauce, miso bean paste) and fermented drinks (wine and beer).
Erythritol is another noncariogenic sweetener (as with all sugar alcohols). Also, it is less likely to cause gastric side effects than other sugar alcohols because of its unique digestion pathway. Its caloric value is a mere 0.2 kcal per gram, making it 95 percent lower than table sugar and other carbohydrates that yield 4 kcals/g.
Produced commercially via yeast fermentation of glucose, erythritol has seen a rapid growth in popularity since 2006. And recent research studies have added another big plus: erythritol shows characteristics of a powerful antioxidant and thus could protect membranes from cellular damage, including the damage characteristic of type 2 diabetes.
Polydextrose is an indigestible synthetic polymer (repeating unit) of glucose. It is considered a soluble fiber by the FDA and therefore used as a replacement for sugar, starch and fat in commercial food applications, such as beverages, breakfast cereals, salad dressings, desserts and dessert mixes, puddings, cakes, candies, gelatins and frozen novelties. Because it acts as a soluble fiber, it functions as a probiotic, while functionally acting as a thickening agent in formulations.
Tagatose, a naturally occurring simple sugar found in small amounts in dairy products and some fruits, is a stereo-isomer of fructose, meaning that it has the same formula as fructose but is shaped differently. It is nearly as sweet as sucrose (92 percent) and has some similar physical properties.
For example, it caramelizes similarly to sugar under high temperatures. Unlike sugar, however, it is much lower in calories -- about two thirds lower than sucrose -- and does not affect insulin. Nor does tagatose promote bacterial growth that causes tooth decay.
Some studies show tagatose could enhance liver glycogen stores and decrease absorption of glucose from the small intestines. Commercially, tagatose is derived from lactose, also known as milk sugar and a disaccharide composed of glucose and galactose.
Ribose is a five-carbon sugar that the body makes as the base of important compounds like DNA, RNA and adenosine triphosphate (ATP), the molecule referred to as the energy currency of the body. Any reaction that requires energy needs ATP. Our bodily stores of ATP are very limited. There's a small backup system of high-energy molecules to help regenerate ATP, but this source lasts only seconds.
There is evidence to suggest ATP-depleted muscles respond favorably to ribose supplementation, implying that it can help muscle cells recover from stress by supplying the base carbohydrate for ATP synthesis. This has the potential to benefit heart patients, increasing the power of heart muscle contractions that send blood on his destination. Ribose is not metabolized as sugar and therefore provides no calories. It is a white powder, about half as sweet as sucrose and is readily soluble in water.
Sugar molecules can be made to take on many different characteristics, depending upon the application and the perceived value to the consumer. Part of that perceived value relates to the status "plain old sugar" has been plagued with.
Pure sugar is a source of carbohydrate minus the nutrients commonly associated with natural foods. As such, it should occupy only a small portion of a healthy diet -- generally about 10 percent of calories or less, according to the Academy of Nutrition and Dietetics and the American Heart Assn. Presently, sugar occupies 14 percent of calories, down from 16 percent in 1970. It can safely be said that the perception of sugar's threat to our health is far greater than the reality.
This article originally appeared in the July 2013 issue of Food Processing Magazine.