Low-Cal Sweet Tooth Satisfaction

If Mary Poppins were around today, its doubtful shed encourage a spoonful of sugar to help the medicine go down. Thats because sugar (sucrose) and similar 4-calorie-per-gram carbohydrate sweeteners have been implicated as contributors to Americas obesity crisis.

Many health advocates have dubbed the 4-calories-per-gram sweeteners as empty calories. However, in many applications, sugar is anything but empty, as sugar performs a host of functions in addition to providing sweetness.

Sweeter than sugar

Todays food designers are challenged with reducing calories, maintaining sweetness and delivering a product that structurally resembles the sugar-sweetened version, often by partial replacement of sugar or other carbohydrate sweetener with a combination of high-intensity sweeteners, polyols and other sweetening agents, including ingredients described as enhancers, herbs and plant extracts.

For example, earlier this year, the Dannon Company, White Plains, NY, introduced Light & Fit 0% Plus, a nonfat yogurt that contains a mere 60 calories per 4-oz. cup. This is achieved through a unique combination of four sweeteners: acesulfame potassium (acesulfame K), aspartame, fructose and sucralose.

Acesulfame K, aspartame and sucralose are three of the five FDA-approved artificial sweeteners. The other two are the recently approved neotame and the longest approvedsaccharin. All five are considered high-intensity sweeteners, with usage levels so low in any application that they contribute virtually no calories.

Uniquely fructose

In Light & Fit 0% Plus, the only caloric carbohydrate sweetener is fructose. Interestingly, fructose also happens to be the sweetest of all naturally occurring carbohydrates. In fact, fructose is 1.73 times sweeter than sugar.

Fructose exhibits a sweetness synergy effect when used in combination with other sweetenerscaloric and noncaloricwith the relative sweetness of the blended sweeteners perceived as greater than the sweetness calculated from the individual components. The heightened sweetness from such a blend means a reduction in calories, because less total sweetener is needed. Of course, if only high-intensity sweeteners are used, calories are even more reduced.

Relative sweetness of fructose in an application depends on the conditions, including temperature, solids, pH and other ingredients. Calorie reduction depends on the sweeteners used in the blend, which is dictated by the flavor and cost objectives of the formulator.

Further, all sweeteners vary as to when they exhibit their characteristic sweet flavor during product consumption, as well as when the sweetness disappears. Most high-intensity sweeteners display a prolonged extinction time referred to as linger. Sweetness linger can be beneficial in applications such as chewing gum, where prolonged sweetness is a desirable quality. However, in some applications, such as yogurt, a lingering sweetness is unpleasant. Further, some high-intensity sweeteners have a delayed sweetness onsetoften advantageous when blending sweeteners.

For example, aspartame has no initial burst of sweetness, but the sweetness lingers. Fructose provides the initial sweetness burst in a fructose-aspartame blend, so aspartame levels can be decreased, thus halting the lingering sweetness.

Besides flavor advantages, fructose contributes solids, which often are required when other caloric-carbohydrate sweeteners, such as sugar, are replaced solely by high-intensity sweeteners. Depending on the application, the solids from fructose can reduce the solids required from other sources, such as low- or non-sweet carbohydrates (i.e., fructooligosaccharides, gums, polyols, starches, etc.) or proteins. That translates into possible cost savings.

Intensely sweet

At 7,000 to 13,000 times sweeter than sugar, neotame is the sweetest of all approved sweeteners. Like other high-intensity sweeteners, the actual sweetness potency of neotame is dependent on its concentration, as well as the matrix in which it is used, says Ihab Bishay, senior vice president, research and development, The NutraSweet Company, Chicago.

Neotame is made of the same two amino acidsaspartic acid and phenylalaninethat comprise NutraSweets original high-intensity sweeteneraspartamewhich is only about 180 times as sweet as sugar. Though neotame is a derivative of aspartame, it is 30 to 60 times sweeter than aspartame, says Bishay.

Neotame is the highest-potency sweetener currently available in the U.S. marketplace, and is also the most cost-effective, says Bishay. Neotame is primarily used to replace a portion15% to 30%of sugar or high-fructose corn syrup, while maintaining the same taste, flavor and overall quality of the product. It reduces total sweetener cost and lowers calories.

Both neotame and aspartame have a more lasting sweetness, continues Bishay, making them well suited in blends with sweeteners perceived very quickly, such as acesulfame K, saccharin or fructose. Products where up to 25% of the carbohydrate sweetener is replaced with either neotame alone or blends of neotame and, for example, acesulfame K, have passed triangle tests indicating they are identical to the full-sugar controls.

NutraSweet research indicates neotame can partially replace more-expensive high-intensity sweeteners in select applications, providing a cost savings to the food manufacturer. Studies have shown that neotame, or blends of neotame and acesulfame K, can replace up to 50% of the sucralose in a formulation without altering the flavor profile or taste characteristics, as judged by a discriminating triangle-test panel, says Bishay.

Made from sugar

Since earning FDA approval in 1998 as a general-purpose sweetener, sucralose has been in demand by food manufacturers because it is the most-heat-stable of the artificial sweeteners, and also has a sweetening profile most like natural sugar, says Stacey Walton, food scientist, Tate & Lyle, Decatur, IL.

However, when demand exceeded supply a few years back, product designers aggressively pursued reducing use levels of sucralose by blending it with other sweeteners. This has become commonplace in the food and beverage industry, especially since sucraloses sweetening effect intensifies when blended with other sweeteners in certain matrices.

Sucralose is manufactured from sugar using a multistep patented process that selectively replaces three hydroxyl units (molecularly bonded hydrogen and oxygen atoms) with chlorine atoms. Sucralose has application in all foodstuffs. It dissolves in clear liquids and does not react chemically with any other ingredients.

Sucralose is described as being 600 times sweeter than sugar. However, at lower usage levels, sucraloses sweetness can double in potency, says Walton. This proves to be very useful in low-calorie formulations where only 20% to 40% of sugar is removed from a formulation. Sucralose readily replaces the sweetness of the removed sugar, while the overall formulation suffers no loss in quality or integrity. We have had great success using this approach when formulating low-calorie beverages, puddings, gelatins, sauces and dressings. Such applications do not require any bulking agents, and there is no perceived change in the sensory profile.

In diet applications where all carbohydrate sweetener must be replaced, it is possible to match the sweetness level by using sucralose, continues Walton. Typically, a bulking agent is also required for applications other than beverages. When trying to match a full-calorie product, it is helpful if the product-development timeline allows for flavor modification.

Fewer calories, with bulk

Numerous other sugar alternatives are available. Some provide bulk in addition to reduced-calorie sweetness. Use varies by application, with many working best in synergy with other sweeteners.

For example, tagatoses physical bulk is similar to sugars, and it is almost as sweet. It only contributes 1.5 calories per gram, since only 15% to 20% of tagatose is absorbed in the small intestine. The major part of ingested tagatose is fermented in the colon by indigenous microflora, thus providing a prebiotic effect.

Tagatose is made via a patented procedure from lactose (milk sugar) in a two-step process. In the first step, lactose is hydrolyzed to glucose and galactose. In the second step, galactose is isomerized to D-tagatose by adding calcium hydroxide. D-tagatose is then further purified by means of demineralization and chromatography. The final product is a white, crystalline substance that is at least 99% pure.

Processing and preparing foods made with tagatose must accommodate certain temperature reactivities, as tagatose-containing products brown and caramelize more readily than sugar-containing foods. Depending on the application, this can be desirable.

Polyols can also lower calories. Sometimes referred to as sugar alcohols because of their molecular configurationpart sugar and part alcoholthese nutritive alternative sweeteners are incompletely absorbed and metabolized by the body, and consequently contribute fewer than 4 kcal per gram.

Many polyols have food applicationerythritol, isomalt, lactitol, maltitol, mannitol, sorbitol, xylitol and moreeach with unique functionalities.

Erythritol, unlike most other polyols, is considered natural. It is about 70% as sweet as sugar, and contains only 0.2 calories per gram. Erythritol has excellent heat stability and can manage water activity in select applications.

Erythritol is rapidly absorbed in the small intestine and eliminated by the body within 24 hours. Thus, the laxative side effects sometimes associated with excessive polyol consumption are unlikely with erythritol-containing foods.

Because of its lower sweetness, as compared to sugar, erythritol is often used in combination with high-intensity sweeteners, especially aspartame and acesulfame K, to take advantage of the synergy.

Surprisingly sweet

Some ingredients in the marketplace are not labeled as sweeteners, yet still provide sweetness or enhance other sweeteners. For example, extracts derived from the leaves of Stevia rebaudiana, an herb in the chrysanthemum family that grows wild as a small shrub in South America, exert varying degrees of sweetness. At the time of this writing, Wisdom Natural Brands, Gilbert, AZ, had declared self-affirmed GRAS for its stevia product. Any product without GRAS status must be labeled as a dietary supplement.

Stevia and its various components are 200 to 400 times sweeter than sugar, depending on the extraction. Various companies are using proprietary technologies to extract compounds from the stevia leaf, turning those extracts into a sweetening ingredient.

For example, Whole Earth Sweetener Company, a subsidiary of Merisant Worldwide Inc., Chicago, developed a sweetener based on rebaudioside-A (reb-A), an all-natural, purified component of the stevia plant. Reb-A has been identified as the sweetest part of the stevia leaf. It is noncaloric and about 400 times sweeter than sugar. The introduction of this ingredient represents the culmination of four years of research and development, notes Paul Block, CEO, Merisant and Whole Earth Sweetener.

Blue California, Rancho Santa Margarita, CA, anticipates receiving GRAS self-affirmation for its proprietary reb-A ingredient, also 400 times sweeter than sugar. Our product is 100% water-soluble and very stable, even at baking temperatures, as well as low and high pH levels, says Cecilia McCollum, executive vice president, Blue California.

Newayceutical Inc. (Neway), New York, markets a line of natural sweeteners derived from the Asian fruit luo han guo, harvested from the Siratia grosvenori plant. Luo han guo extracts can be about 300 times sweetener than sugar and contain zero calories.

The companys proprietary formula uses the whole fruit. The sweetness comes from the structures unique to luo han guo called mogrosides, says Abby Dress, marketing and operations consultant to Neway. Luo han guo is considered a food ingredient in the United States, as it was discovered and identified in the 1930s and noted by USDAs Bureau of Plant Industry in 1941.

Beyond sweeteners

Ingredients that arent sweeteners but enhance sweetness are another option. For example, Wixon, Inc., St. Francis, WI, markets a flavor that has a synergetic effect with sugars, thus enhancing the natural sweet taste without adding calories, says Mariano Gascon, vice president of R&D. He notes that its intended to amplify the sweet taste of the sugar in a food or beverage, so you would need less sugar and still get the same sweetness that you desire.

Taste tests conducted by Wixons sensory team show that the ingredient can enhance the sweet taste of cereals and cookies, as well as powdered drink mixes and other beverages, notes Gascon. Because some sugars need to be present in the product, and it cant be used with high-intensity sweeteners alone, the ingredient is suitable for use in desserts, cereal, granola bars, yogurt, beverages, baked goods, jams and more.

Usage levels are relatively lowbetween 0.05% and 0.20%, says Gascon. That means product reformulation is not required. It appears on the ingredient statement simply as natural flavor, he says.

Senomyx, Inc., San Diego, is working with a new sucrose enhancer that maintains sweetness with up to 50% sugar reduction in select applications. It has the potential to be used to enhance the sweet taste of sucrose in numerous food and beverage products, says Kent Snyder, president and CEO, Senomyx.

Senomyx is also completing development activities with a sucralose enhancer to enable up to a 75% reduction of sucralose in select applications while maintaining the same sweet intensity without off tastes.

With all these sweetening options, maybe someone can just make the medicine taste better so it does goes down easier.

Donna Berry, president of Chicago-based Dairy & Food Communications, Inc., a network of professionals in business-to-business technical and trade communications, has been writing about product development and marketing for 13 years. Prior to that, she worked for Kraft Foods in the natural-cheese division. She has a B.S. in food science from the University of Illinois in Urbana-Champaign. She can be reached at [email protected].