Consumers and food companies understand that dietary fiber provides a healthy, sustained glycemic response to glucose spikes. Fiber applications can be a boon to the millions of Americans who are controlling their carbohydrate consumption.
Oatmeal is a rich source of soluble fiber.
Photo by PhotoDisc.
But there is a long way to go. According to the American Dietetic Association (Chicago), most Americans consume less than half of the recommended 25 g of fiber daily.
And food manufacturing behemoths are being parsimonious with fiber content. In an October 22, 2003, Wall Street Journal article, reporter Michael J. McCarthy noted that "from breakfast to dinner, fiber is disappearing from the American diet, as high-margin, eat-on-the-go packaged foods replace basic foodstuffs."
FIBER'S HEALTH FACTORS
With the exception of the 1990s oat bran craze, fiber has rarely received the attention it deserves.
During the 1970s and 1980s, dietary guidelines were more concerned with fat and cholesterol consumption. As late as 1990, the United States Department of Agriculture (Washington, DC) advised that populations with diets low in dietary fiber and complex carbohydrates and high in saturated fat "tend to have more heart disease, obesity, and some cancers. Just how dietary fiber is involved is not yet clear."
Today, research continues to illuminate the benefits of fiber consumption. A recent meta-analysis in the February 2004 issue of the Archives of Internal Medicine by researchers at Harvard University found that for each 10-g-per-day increment of fiber consumption, there was a 14% lower risk in coronary heart disease events, and a 27% lower risk of fatal coronary events.
Further, in the February 2004 issue of Diabetes Care, researchers reported that consumption of whole-grain foods was associated with a lower risk of developing a condition known as metabolic syndrome. Metabolic syndrome, which is marked by extra belly fat, low HDL levels, and high triglycerides and blood pressure, is sometimes used as a predictor of cardiovascular disease and adult-onset type-2 diabetes.
CAN FOOD ADAPT?
The typical hectic life-styles of Americans, and their desire for ultimate convenience, continue to support the demand for quick-and-easy processed meals. The onus is on food manufacturers to incorporate a higher fiber content into their products, while keeping in mind a quality carbohydrate approach.
"Manufacturers have learned that consumers prize convenience and are unlikely to adapt to new eating or dosing regimens," says Greg Stephens, vice president of sales and marketing for Nurture Inc. (Devon, PA).
Galactomannan from fenugreek is a slow-carb fiber that promotes the gradual absorption of glucose into the bloodstream.
Photo by Steven Foster Group Inc.
Quality carbohydrates are low glycemic, meaning that they break down slowly, causing a more controlled and gradual release of glucose into the bloodstream; this action also promotes quicker feelings of satiety. By contrast, high-glycemic carbohydrates promote a rapid glucose release that floods the bloodstream. A diet that consistently creates such spikes has been shown to promote diabetes and obesity.
Overall, observes Steven Young, PhD, technical advisor for Matsutani America Inc. (Decatur, IL), fiber inclusion in foods is thought to promote intestinal health as well as "secondary effects such as reduction in certain types of cancers, reduction in serum lipids, moderation of blood glucose levels, and maintenance of beneficial intestinal microflora."
Dan Best, marketing director at Pizzey's Milling (Angusville, MB, Canada), adds that many dietary fibers also contain nutraceutical components with antioxidant, prebiotic, and probiotic qualities. "Such nutraceutical components increasingly will be viewed as important dietary fiber adjuncts," he predicts.
FIBERS AND APPLICATIONS
The use of soluble fibers in the United States has grown rapidly during the past year, says Jim Kappas, director of international marketing at Cargill Health & Food Technologies (Minneapolis). He attributes the steady growth to the inclusion of fiber in nutrition and cereal bars, yogurts and dairy products, and nutritional beverages such as smoothies.
"The acceptance of reduced- and low-carbohydrate baked goods is also adding to the growth and acceptance of fibers in foods by U.S. consumers," he says.
"Many manufacturers are seeking to add dietary fiber to lower net carbs in low-carb food products," says Jocelyn Mathern, RD, technical specialist for Acatris USA (Minneapolis). "This is a novel application for fiber."
Manufacturers are not only using these ingredients as a means of increasing daily fiber intake and addressing controlled carbohydrate consumption, but also "as a means of modulating texture and mouthfeel with food and beverage formulations," points out Donald Cox, PhD, business development manager of food ingredients at DKSH North America (Baltimore).
Within the past couple of years, several raw-material suppliers have launched a variety of dietary fiber substances for inclusion in numerous foods and beverages that address the aforementioned health issues. These fibers come from a wide variety of sources, such as oats, fenugreek, bamboo, and flaxseed; each has its own properties and characteristic profile.
In addition to omega-3 fatty acids and lignans, flaxseed provides both soluble and insoluble fiber.
Photo by Steven Foster Group Inc.
For instance, inulin, considered a "free carbohydrate," is a natural soluble fiber that cannot be digested, explains John Martin, project leader for Orafti Active Food Ingredients (Malvern, PA). In the past, it was used more for functional rather than nutritional benefits, such as bar softening, creating a desirable mouthfeel, flavor masking, and replacing sugar and fat. More recently, inulin has been sought for its zero-net-carb profile, which is used by some manufacturers to replace high-carbohydrate ingredients like sugars and flours.
"Typically, formulators use inulin at approximately 8 g per serving," Martin says. For label claims, approximately 2.8 and 5.6 g per serving of inulin are needed for "good source" or "excellent source" of fiber claims, respectively. He adds that only 2 g per serving of Orafti's Raftilose Synergy 1 is needed to make the label claim that inulin "boosts calcium absorption."
Oliggo-Fiber inulin, from Cargill Health & Food Technologies, may help promote bone health by increasing calcium absorption, notes Kappas. "It also provides a creamy mouthfeel in dairy and beverages and can help increase shelf life in nutrition bars and baked goods."
Matsutani's Fibersol-2, a digestion-resistant maltodextrin derived from cornstarch, contains more than 90% indigestible carbohydrate but is completely water soluble. Fibersol-2 is odorless, flavorless, and colorless; has low viscosity; and is stable through processing, packaging, and distribution conditions, Young says. In addition, the product enables the use of various nutrient content claims. Products with 2.5 g of fiber per serving (or 2.9 g of Fibersol-2) may be labeled a "good source of fiber," while products with 5 g of fiber (or 5.8 g of Fibersol-2) may be labeled an "excellent source of fiber," and products with more than 5 g of fiber may be labeled "high," "enhanced," or "fortified."
Oat bran rode a wave of popularity about a decade ago, and back then many consumers were made aware of its exceptional cardiovascular benefits. Nurture's Stephens notes that OatVantage oat bran concentrate is a low-glycemic-index soluble fiber derived from oats that has been shown to reduce LDL and total cholesterol and help manage healthy blood glucose levels. OatVantage is standardized to contain 54% beta-glucan and supplies 17 times more beta-glucan than common oats.
A major clinical study of the cardiovascular benefits of OatVantage was completed at the University of Minnesota (St. Paul, MN) by researcher Joanne Slavin, PhD, RD, who presented the results at SupplySide East this month in Baltimore. A new study investigating its benefits in glycemic and insulemic responses has recently been initiated.
OatVantage is suitable for ready-to-drink and dry-mix beverages, semisolid and solid foods, chews and confections, and dietary supplements. Notable applications include dairy beverages with extended shelf life and other ready-to-drink beverages, such as retort, aseptic, and ultra-high-temperature processing drinks, as well as nutritional bars with moist textures, he adds.
Another ingredient, wheat bran flour, is the result of a cost-effective method one Canadian company uses to deal with the normal by-products of its wheat flour production. Hayhoe Mills (Woodbridge, ON, Canada) launched Avignon low-net-carb wheat bran flour in November. According to company president Mark Hayhoe, the wheat bran flour is mostly fiber and is therefore low in carbohydrates. It is also more absorbent than conventional flour, which helps bread products stay fresh longer, he adds.
Bamboo is the source of CreaFibe QC, a dietary fiber that consists of more than 90% water-insoluble fiber from CreaFill Fibers Corp. (Chestertown, MD). This versatile fiber is also free of taste, color, and odor. It is more hydrophilic than lipophilic, and its molecular structure allows the formation of high amounts of additional hydrogen bonding.
This combination, says Sara England, national business manager at CreaFill, "restricts the displacement of water by fat during frying. So, by including even a small percentage of CreaFibe QC in batter formula, the fat content can be reduced significantly, by as much as 2%."
Another benefit of this fiber is that it facilitates extrusion. In the presence of moisture and heat and when added to dough, cellulose fibers form complexes with starch. The improved moisture control results in dough that is less sticky. The benefit is increased extrusion rates and potential calorie reduction of end products. Food applications, England points out, run the gamut of snack foods, nutraceuticals, dairy foods, frozen foods, and sauces.
"Today more than ever, consumers are seeking low-calorie, high-fiber foods that are also tasty," adds England.
DKSH North America, notes Cox, is working with a small group of companies to develop novel fiber sources. One example is Fibergel's (Mundelein, IL) Z-Trim, which is based on amorphous cellulose fiber with high water-binding capacity and increased functional performance. It can be used as a fat replacer that reduces calories and increases the fiber content of food products.
PolyCell Technologies (Crookston, MN), another DKSH partner, offers two beta-glucan materials. BBG Concentrate is 23% beta-glucan from barley and is suitable for nutrition bars and dairy-based beverages. Glucagel contains more than 80% beta-glucan and has a high percentage of soluble fiber, which creates gel-forming characteristics for a wide range of consumable options.
In 1908, a physician recommended to entrepreneur Lafayette Coltrin that he add flaxseed to his diet. Coltrin sprinkled flaxseed on his whole-wheat flakes for breakfast and created Uncle Sam cereal, which, in 2004, has a prominent "Low Glycemic" seal on the box. "Whole flaxseed offers many nutritional and nutraceutical benefits, including omega-3s and lignans," says Pizzey's Best. "It also contains less than 3% net carbs, making it a useful, cost-effective ingredient in the development of low-net-carb foods."
Lignans, he explains, are intimately associated with the dietary fiber fraction in flaxseed. The 1% lignan content of whole flaxseed increases to 6% in flaxseed bran. Whole flaxseed provides significant levels of dietary fiber—10% soluble and 17% insoluble. "The soluble-fiber fraction in flaxseed provides lubrication in some formulas; it can be used to replace oils or shortenings in certain bakery formulations, thereby eliminating trans fats," he states.
Pizzey's Milling has developed a particular flaxseed formula for flaxseed beverages. Only 2.2% flaxseed added to soymilk or juice will contribute 1560 mg of omega-3 essential fatty acids, 70 mg of lignans, and 1.3 g of dietary fiber per serving. In addition, Pizzey's has used flaxseed at 15% (wet basis) in pizza crust formulations and 30% (flour basis) in breads to reduce net-carb value to well below 10 net carbs per serving.
Fenugreek galactomannan is also a "slow-carb" fiber that promotes gradual absorption of glucose into the bloodstream, according to Acatris USA's Mathern. The company's FenuLife, an odorless galactomannan extract derived from fenugreek seed that is standardized to 85% total fiber, can help promote glycemic balance, she says. When consumed with a meal, the galactomannan forms a gel in the stomach that helps slow down gastric emptying and thickens intestinal contents, resulting in delayed glucose absorption and decreased postprandial blood sugar spikes. FenuLife is suitable for use in dietary supplements, nutrition bars, and powdered beverages.
Raw-material suppliers have worked diligently to ensure that the physical properties of their varied fiber ingredients are versatile enough to provide the nutrition and smart carb profile desired by a growing number of American consumers. In other words, fiber is fashionable again!