High-protein "meal replacement"
bars may utilize both fat
replacers and sugar substitutes.
By Frances Katz, Senior Technical Editor
Fat and sugar are a dangerous mixture. When combined, these ingredients have the ability to trigger obsessive behavior -- as anyone who has stared down a warm, melty, butter-laden chocolate chip cookie will attest. While their unenviable position atop the old Food Guide Pyramid affords them only about 10 percent of the real estate, a disproportionate 40 percent of Americans’ total calories come from that spot.
It’s no surprise, then, that cutting fat and sugar in the American diet is among the top 2005 program priorities of the FDA’s Center for Food Safety and Applied Nutrition. Nor will it be a surprise if that effort takes up most of the time and effort of most R&D departments.
Cutting fat and sugar is big business. Demand for high intensity sweeteners and fat replacers is expected to amount to $1.2 billion in 2004, when all the figures are in, with high intensity sweeteners growing at about 2 percent per year. Fat replacers are growing at about 7 percent per annum, according to a recent report from the Freedonia Group (www.freedoniagroup.com
To replace sugar and/or fat, the whole formulation comes into play. Sugar and fat replacers come in several types, some appropriate to certain applications and others less so.Fat replacers and mimetics
Probably the earliest fat replacer was starch. It was cooked into a paste and introduced with egg and oil into an emulsion commonly called spoonable salad dressing, which was a low-cost replacement for mayonnaise.
Starch products are still used as fat replacers, along with their derivatives maltodextrins, corn syrups and similar products. But new products, based on rheology and particle size distribution studies, have provided protein-based fat replacers (which reduce calories per gram from 9 to about 4) as well as rearranged fats that are not easily digestible by human enzymes.
Fat replacements -- products that can replace fat’s frying qualities as well as the functions of fat in baked goods, dairy, and dressing/sauces -- generally are formed on a backbone of a fatty material such as glycerol, polyester or sorbitol. They are metabolized to different degrees, and some (the completely unabsorbed materials like Olestra) may cause temporary gastric difficulties, and may affect oil-soluble vitamins, unless this is factored into the formulation.
|While their unenviable position atop the old Food Guide Pyramid affords fats and sweets only about 10 percent of the real estate, a disproportionate 40 percent of Americans’ total calories come from that spot.|
Even with much effort going into fat replacement, the most popular reduced fat foods are those that are relatively simple. According to a recent poll by the Calorie Control Council, among consumers concerned about fat, 62 percent use reduced-fat dairy foods, 50 percent try reduced-fat cheese, sour cream and yogurt, and 56 percent buy reduced- or fat-free salad dressings or sauces. Only 19 percent of lipid-conscious consumers opt for low-fat candy, and 36 percent use reduced-fat ice cream and frozen desserts.
While replacements generally can be used pound-for-pound of fat, there is a second class of products called mimetics, which replace some of fat’s key characteristics in certain applications.
Carbohydrate-based fat mimetics tie up additional water in a formula to replace the bulk of fat. These products can’t replace frying oil and work best in emulsions, such as salad dressings, baking batters and dough products.
Current emphases are on fiber, which reduces the calorie count, beta-glucan soluble fiber and polyols (which are also sugar replacers), because the caloric content can be reduced while maintaining water activity. These products all replace part of a lipid phase with a water phase, so water activity becomes extremely important to maintaining shelf life.
Protein-based fat mimetics can be used in dairy products, baked goods, dressings and sauces, reduced-fat meats and soups. They generally include egg albumen, corn zein, and whey. They may be produced by microparticulation, controlled thermal denaturation or a combination of systems to produce a functional protein that has the “slip” and mouthfeel of fat.Sugar substitutes
According to the previously mentioned Calorie Control Council poll, 79 percent of the U.S. adult population (or 163 million Americans) use low-calorie and sugar-free foods and beverages. Two-thirds of Americans use such products several times a week or more.
There are currently five low- or no-calorie sweeteners approved by the FDA: acesulfame potassium, aspartame, neotame, saccharin and sucralose. There also is a number of reduced-calorie sweeteners (polyols) available in the U.S., including erythritol, hydrogenated starch hydrolysates, isomalt, lactitol, maltitol, mannitol, sorbitol and xylitol.
“Low-calorie and sugar-free products can be part of a healthy diet, as supported by the [American Dietetic Assn.’s] updated position statement. Research shows consumers find such products helpful and would like to see more developed,” says Lyn Nabors, executive vice president of the Calorie Control Council.
Like fat replacement, sugar replacement attempts to match various properties of sugar. If only sweetness is needed, there is a number of replacements that can do the job.
Saccharin is the granddaddy of the lot, dating back all the way to 1879. It’s available in three forms: sodium saccharin, which is highly soluble; acid saccharin; and calcium saccharin, which is used in reduced sodium products. It’s 300 to 500 times sweeter than sucrose. It has been largely replaced in processed foods by newer products that have little of the bitterness associated with saccharin, but it remains a popular coffee sweetener in packets.
Acesulfame potassium â acesulfame K or ace-K -- is good for foods that are not baked or heated above 200Â°F. Ace-K is 200 times sweeter than sugar. It is sold under the brand name Sunett by Nutrinova Inc. (www.nutrinova-na.com
), Somerset, N.J., a business unit of Celanese AG. Although a key patent expires in March, Nutrinova also holds two patents on intermediates in the manufacturing process of ace-K, which are valid in the U.S. until 2008, and more than 30 additional patents on the processes.
FDA first approved acesulfame potassium for dry uses in 1988 and has increased product approvals for use in about 20 product categories in the U.S. These include chewing gum, candy, desserts, baked goods, yogurt, gelatin and as a tabletop sweetener. Acesulfame potassium is approved for use in more than 4,000 products in about 90 countries.
Aspartame, best known as tabletop sweetener Equal or NutraSweet, was discovered by G.D. Searle & Co. in 1965 and introduced as a sweetener in 1981. It now is now sold by a number of companies, including the Nutrasweet Co. (www.nutrasweet.com
) and the once-related Merisant Co. (www.Merisant.com
), both based in Chicago. Aspartame is about 200 times as sweet as sucrose and delivers less than a half-calorie per gram.
A new form of aspartame is claimed in a patent from Ajinomoto Food Ingredients (www.ajiUSA.com
), Chicago, in the form of a crystal instead of an amorphous material that requires blending. According to inventors, the crystal form is of high purity and stability.
The newest sweeteners
|New varieties of Kool-Aid Jammers carry the American Diabetes Assn. seal on the front and both sucralose and acesulfame potassium in the ingredient panel. They have just 10 calories per pouch instead of 60 calories in the varieties sweetened with high-fructose corn syrup.|
NutraSweet Co.'s new sweetener, neotame, was approved by FDA in 2002, and is some 7,000 to 13,000 times as sweet as sucrose. In just two years, its use has exploded, according to Ihab Bishay, senior vice president of research, with use in Ice Breakers breath mints, Roman Meal low-carb bread, Mayfield Dairy milk products and a number of other products, both internationally and domestically.
“It’s often blended with sugar or high fructose corn syrup to reduce cost or improve the flavor and sweetness profile,” says Bishay. “It can be used with bulking agents to provide sweetness at very low levels. It doesn't have to carry an information statement for phenylketonurics, as the product doesn't metabolize to phenylalanine. It provides an intense, clean sweetness at very low levels.”
Sucralose is sold by Johnson & Johnson subsidiary McNeil Nutritionals LLC (www.splenda.com
) under the brand name Splenda, but is manufactured by London-based Tate & Lyle Plc. It is 600 times as sweet as sucrose and is unabsorbed by the body.
Recent work by Johnson & Johnson scientists have looked into combinations of sucralose with fiber. But, says William Chapello, principal scientist for McNeil Nutritionals in New Brunswick, N.J., the American public has a problem tolerating fiber. He and associates at McNeil developed a product that included high intensity sweeteners and inulin, with the latter helping the digestive tract accept fiber.
Chapello also told of a product called Sugar Blend, which contains sugar and Splenda. It is designed to replace the sugar in products such as baked goods at about 40 percent of the amount called for in a recipe. “It will have the full sweetness of sugar, and enough of the technical functions of sugar to produce moist, flavorful baked goods,” he says. Just introduced during the last quarter of 2004, it’s too soon to tell how the product will fare, but, says Chapello, “the initial demand is good.”Bulking up
While it’s not much of a sweetener, fiber replaces the bulking quality of sugar. Louise Slade and Harry Levine, research fellows at Kraft Foods Inc. (www.kraft.com
Slade and Levine were creators of several generations of products for General Foods, Nabisco and now Kraft, introducing the food polymer science approach to moisture management 25 years ago. “The key to such products is healthy fiber,” says Levine, “and the resistant starch also improves baking characteristics.”
These high-intensity sweeteners may be used directly in beverages if mouthfeel, texture and water activity are not issues. If viscosity and water activity are critical, the high-intensity sweeteners are blended with non-sweet bulking agents to effect those characteristics. Polydextrose and more recently, fiber, are typical products used to bulk high intensity sweeteners without adding carbohydrate calories.
Other sugar replacers, including polyols and trehalose, are used to reduce the amount of sucrose in products. These products have fewer calories than a similar amount of sucrose. Trehalose, offered by Cargill Health & Food Technologies, is replaceable pound-for-pound with sugar, but because it metabolized differently, it provides only about 1.3 calories per gram.
Erythritol, a polyol that was recently approved in Canada (it has been approved in the U.S. since 1997) produces 0.2 Kcal/g. It provides body to foods and is approved for use in beverages, chocolate and confections, baked goods, sauces, ice cream, yogurt, salty snacks, fruit fillings, icings, cookies, bars, breakfast cereals and other products.
“Eridex [Cargill’s brand of erythritol] really took off with the low-carb craze of last year because it contributed virtually no calories, has no contribution to blood sugar, has very high digestive tolerance (2-4 times the tolerance of other polyols and higher tolerance than even many nutritive sugars like lactose and crystalline fructose) and is naturally occurring and naturally produced,” according to Ron Perko, business development manager for polyols at Cargill Food and Pharma Specialties (www.cargill.com
), Minneapolis. “With the current emphasis on obesity and diabetes, we are seeing more interest in reduced-calorie products and products with a lower glycemic load.”
|NOTE TO PLANT OPS|
Producing low-sugar and/or low-fat products generally means a new approach to formulation. In today's atmosphere, it means formulating a healthy product and adding appropriate ingredients to ensure it tastes good. The manufacturing plant will depend heavily on the development team for initial production, because these products likely will be very different from the products they may replace.
A low-fat product that contains a starch or gum-based mimetic may need different mixing conditions. For instance, it may require more careful pumping actions to avoid breaking an emulsion that is different from the emulsions in a fat-containing product. Heating requirements may be different as well, especially for a product that is sterilized by heat. Fat conducts heat differently than a water-phase with carbohydrates. If the product is retorted, for instance, this may require new heat penetration studies.
A low-sugar product that contains high-intensity sweeteners will need to be processed to the temperature requirements of the new sweetener, and the absence of sugar may change the heating parameters for flavor retention. In other words, it’s a whole new ballgame. Times and temperatures, pumping pressures and holding times will have to be revisited. Packaging may need different structures to maintain the new product, and even the outside carton may need revisions. Don’t think of this product as a line extension, any more than you’d think of baseball as a replacement for football.