The food-fi ber market in the United States could reach $495 million by 2011, according to new analysis from Frost & Sullivan, a global growth consulting company. In its report, Strategic Analysis of the United States Food Fiber Industry, it noted that the food-fi ber industry earned revenue of $193 million in 2004, with insoluble fi ber accounting for more than $176 million. Interest in soluble fi ber is rising fast, however, and it is estimated that within the next fi ve years, its growth could increase twice as fast compared to insoluble fi ber.
Why is the market for fi ber expected to grow so dramatically over the next few years? That is certainly a fair question when considering how dietary fi ber has been traditionally perceived both by food manufacturers and by consumers. In fact, I still remember from the late 1980s that Saturday Night Live mock commercial about a new bran cereal, “Colon Blow.” That skit captured perfectly the perception of fi ber as “roughage,” a fecal bulking agent that was considered from a dietary or nutrition point of view as less than signifi cant, but certainly had a specifi c purpose that was ideal for satirizing.
Emerging research is changing that point of view, illustrating the value of dietary fi ber in a number of ways that go well beyond traditional perceptions of fi ber and its benefi ts. The studies are also making important distinctions in terms of the health and functionality benefi ts that are provided by the different kinds of fi ber—insoluble fi ber, soluble fi ber, and, at least from a physiological perspective, resistant starch. Furthermore, the different origins of fi ber may also play a part in the kinds of benefi ts that are promoted. For example, beta-glucan soluble fi ber from oats has been shown to reduce blood cholesterol, and is validated by a Food and Drug Administration claim. An interest in barley’s potential health benefi ts has also led to some interesting ingredient developments.
Many of the foods in the health spotlight today happen to be high in fi ber—a fact which is adding polish to fi ber’s image. A rising interest in whole grains, low-glycemic-index foods, weight- and energy-management products, and high-fi ber sweetener alternatives are all fueling the development of new fi ber-based ingredients for use in a broader range of foods and beverages. These developments are also helping to overcome functionality challenges so that the incorporation of fi ber is having less of an impact on taste, texture, or appearance of the fi nished product. From a functionality standpoint, this “invisibility” becomes an integral part of fi ber’s new image.
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In the marketplace, we’re seeing several signs of the growing presence of fi ber. For example, an 8-oz serving of new Old Orchard Brands Healthy Balance Prune Juice Cocktail contains 65% less sugar and 25% more fi ber than the leading brand of 100% prune juice. Two new brown rice products, Uncle Ben’s® Ready Rice® Chicken Whole Grain Brown and Uncle Ben’s Fast & Natural™ Whole Grain Instant Brown Rice, provide natural sources of fi ber. Kellogg initiated the Fiber Challenge, a new initiative designed to promote its fi ber-rich cereal products. And other examples include several Sara Lee brands made with combinations of resistant starch and other fi bers; the fi rst nationwide fi ber-added orange juice launched by PepsiCo; and Dannone’s prebiotic yogurt which contains a soluble fi ber.
Although fi ber’s marketing opportunities are increasing, Americans still consume only about half of the recommended targets of 28 g for women and 35 g for men of dietary fi ber per day. One possible reason for this current “fi ber gap” in the United States may be that consumers are not yet satisfi ed with the taste or overall quality of past products. If so, perhaps the many new additions to the marketplace will change that. Another possible explanation is that food professionals have not suffi ciently promoted the benefi ts that fi ber offers in their products.
In this article, a sidebar (see page 46) addresses the need for a more formalized defi nition for fi ber. But along with this defi nition, a need may exist to spell out to the consumer why fi ber is being used in that product and what benefi ts it is bringing to the table. For example, is fi ber being used as a prebiotic to maintain a healthy intestinal fl ora? Is it being used to reduce blood cholesterol? Is it being used for its weight-management or low-glycemic potential? Or it is being used for its functionality value? Without a clearer linking of fi ber intake to the benefi ts that fi ber is offering in that product, consumers might view fi ber as simply fi ber with its traditional associations. Hopefully that will not happen.
This article will look at a number of fi ber-based ingredient developments and the benefi ts they bring to a formulation. It will discuss how these benefi ts are opening up new opportunities, especially in the areas of fat replacement, texture and sweetness modifi cation, and low-glycemic-index foods; how fi ber can be incorporated into a broader range of applications; and how these developments are shaping fi ber’s image.
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New Name, More Benefi ts
What better way to give fi ber a fresher image than through a new brand name conveying the benefi ts of inulin and oligofructose. Orafti Active Food Ingredients, Malvern, Pa. (phone 610-889-9828, www.orafti.com), did just that when it united its products under one brand, Beneo™.
Previously, scientifi c and nutrition communities recognized Orafti’s products generically as inulin and oligofructose. Food manufacturers accessed them according to their proprietary brand names, Raftiline® and Raftilose®. Consumers in many parts of the world identifi ed the health benefi ts of these ingredients through the Beneo trademark on retail product labels. Now this designation will offi cially bring together the ingredients under one umbrella, allowing the company’s overall message of better nutritional choices to be more readily recognized and understood.
The new brand name will help refl ect the broadening benefi ts that inulin and oligofructose provide. For example, in a recent study, scientists at Leatherhead Food International created a new range of lower-glycemic-index ice creams using 15% Beneo prebiotic ingredients or different types of sugar replacers. The ice creams gave a glycemic response which was 70% lower than the glycemic response produced after eating traditional ice cream.
These ingredients are best known for their prebiotic function, improving gut health and well-being. They also have the ability to replace dietary fat without sacrifi cing mouthfeel and to replace sugar without affecting taste. Functionality tests have shown that inulin can be used to stabilize water into a creamy structure with the same mouthfeel as fat. Using small amounts of the ingredient improves the taste and texture of low-fat ice products such as ice cream. It gives a better balanced fl avor, provides more body and mouthfeel, and stabilizes emulsions and dispersions.
Citrus Fiber Binds Water
A dietary fi ber whose main primary function is not as a dietary fiber?
That’s how Citri-Fi, a new fi ber-based ingredient from citrus pulp, is being promoted by its manufacturer, Fiberstar Inc., Willmar, Minn. (phone 320-231-1829, www.fiberstar.net). Although a source of dietary fi ber, the ingredient serves as an effective moisture management tool. It reportedly attracts, binds, and manages high levels of water—up to 12 times its weight—in baked goods, ground meat and poultry products, and sauces.
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Citri-Fi enables the incorporation of a signifi cant amount of additional water, in a tightly bound form, into food products without increasing the level of free water in the product. It can also be used to absorb and bind existing free water or oil in food products. The tightly bound water or oil held within the fi ber matrices reduces gumminess and syneresis, while enhancing product quality and sensory characteristics, including structure and mouthfeel. Shelf life of products made with the ingredient can be extended.
Because of its functionality properties, the ingredient can be used as a partial shortening and oil replacement in bakery products, such as breads, buns, muffi ns, cake, cookies, tortillas, and pizza crust. At a 50% reduction of fat, studies reported no differences between products containing the fi ber and full-fat versions.
Systems Approach Creates New Fiber-Enriched Cereals
The adoption of a systems approach, where ingredient suppliers use a wide range of ingredients, usually from their own portfolios, to develop fi nished products that demonstrate the benefi ts of these ingredients, can help shape fi ber’s image.
For example, fi ber-enriched breakfast cereals can be created using two new “Ingredient Solution Sets” developed by Tate & Lyle, Decatur, Ill. (phone 217-423-4411, www.tateandlyle.com). The two formulations, available in dry powdered form, contain an optimized combination of functional ingredients such as oat fi ber, modifi ed food starch, and sucralose. They are dry blended with other dry ingredients prior to extrusion or are metered into the extruder by a secondary feeder.
Breakfast Cereal Enrich™ 701 delivers 36% total dietary fi ber (dry basis) with a typical moisture content of 8%. It is used at approximately 14% in a multigrain or whole-grain formula, and allows the fi nished product to meet the “good source of fi ber” claim.
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Breakfast Cereal Enrich 702 delivers 50% total dietary fi ber (dry basis) with a typical moisture content of 7%. It is used at approximately 18% in a multigrain or whole-grain formula, and allows the fi nished product to meet the “excellent source of fi ber” claim.
Both formulations deliver 8 g of whole grain/30-g serving while providing a light and crispy texture with optimum expansion. In addition, cereals made with these formulations have a good mouthfeel without chalkiness from fi ber. The ingredient solutions are designed to work with coated and uncoated breakfast cereals, and with a variety of flavoring systems.
Resistant Starches Reinvigorate Fiber Message
A natural resistant starch, Himaize ® 5-1 Fiber, offers a number of health benefi ts, especially in the management of weight, glycemic index, energy, and digestive health. The ingredient, offering the properties of soluble and insoluble fi bers as well as additional benefi ts, is being promoted as a special class of fi ber by National Starch Food Innovation, Bridgewater, N.J. (phone 908-685-5000, www.foodinnovation.com).
Although resistant starches are not a new ingredient, their rediscovery has recently added a new dimension to the image of fi ber and the benefi ts that fi ber can bring. By its name 5-1, this ingredient is being actively marketed as offering a number of health benefi ts based on more than 120 studies. The fact that it delivers properties of both types of fi ber adds to its distinctiveness.
Hi-Maize also provides a broad range of functionality benefi ts. Its low water-holding capacity is especially important when processing doughs and batters. As a substitute for fl our, it does not change handling characteristics during processing. It also means reduced cooking times or temperatures when compared to foods made with high water-holding fi bers. The ingredient is easily incorporated into a broad range of low-moisture foods without compromising taste, texture, or appearance.
Derived from high-amylose corn, the starch can provide improved yield in breads, higher crumb moisture content in cookies, increased crunchiness and bowl life in cereals, crispiness in sheeted goods, and al dente texture in pastas. It helps food marketers differentiate their products in the marketplace while imparting signifi cant health benefi ts.
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Resistant starch is also being derived from a variety of other sources as well. ActiStar™, derived from tapioca root, is available from Cargill Food & Pharma Specialties, Cedar Rapids, IA 52406 (phone 319-399-2111, www.cargillfoods.com). The starch provides 80% total dietary fi ber and has a low water-holding capacity, permitting high levels of inclusion. Tapioca is said to be the blandest of all the starches, and the ingredient does not detract from the desired taste, texture, or appearance of the fi nished product.
Recently, MGP Ingredients, Inc., Atchison, Kans. (phone 913-367-1480, www.mgpingredients.com), started marketing a new potato-based resistant starch, MGPI FiberStar™ 80 ST, for delivering a minimum of 80% total dietary fi ber in food products. Under terms of an agreement with Penford Corp., the ingredient will be produced by Penford using patented processes exclusively licensed to MGPI. Prior to this new ingredient, MGPI was producing and marketing FiberStar 70, a wheat-based resistant starch. Both products have water-holding capacity that is signifi cantly lower than that of fi ber source such as wheat bran. In addition, these starches possess clean fl avor, are extremely white in color, and impart a smooth, creamy texture, in contrast to many traditional fi bers.
Portfolio Refl ects Sources of Fiber
The importance of fi ber and its ongoing expansion of benefi ts are refl ected by a number by carbohydrate-based ingredients from Cargill, Wayzata, Minn. (phone 952-742-5928, www.cargill.com).
MaizeWise™, a new line of whole-grain corn and corn-bran products, may be used in cereals, pasta, breads, tortillas, taco shells, and extruded snacks. An insoluble fi ber, corn bran boosts dietary fi ber at low-to-moderate inclusion rates, while providing minimal impact to fl avor, texture, and processing characteristics. The products can be used as a direct replacement for existing corn meal, masa, or corn fl ours, or blended with other ingredients.
GrainWise™, an ingredient derived from the aleurone layer of the wheat kernel, contains 45% dietary fi ber and other desirable whole-grain nutrients. Because it has less pigment and fl avor, it can be incorporated into foods at higher levels than full bran. It replaces a portion of the enriched white fl our in product formulas. A typical inclusion rate of 20% gives foods a nutrition profi le similar to that of whole wheat, without affecting the qualities of soft texture, high volume, mild taste, and light color found in breads, pastas, and cereals. It also raises the fi ber content of foods to a level that allows manufacturers to promote fi ber content claims on their labels.
Other fi ber sources include Oliggo-Fiber® inulin and the Acti-Star family of resistant starches.
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Polydextrose Creates New Beverage Opportunities
Fiber enriching a clear beverage? That is only one of the many innovative beverage formulations supplemented with fi ber that can be produced using Litesse polydextrose from Danisco Sweeteners, Ardsley, N.Y. (phone 800-255-6837, www.danisco.com/sweeteners). The highly soluble, low-glycemic carbohydrate, which is 90% fi ber, offers a variety of benefi ts in beverages that are low calorie, sugar free, and fi ber enriched.
Low-calorie, no-sugar-added enhanced waters are one of the newest ways to add soluble fi ber to the diet, taking advantage of the popularity of this beverage segment. For example, Diet Peach-Flavored True Water utilizes a 70% solution of Litesse® Ultra to provide 3 g of dietary fi ber for every 8-oz serving. The ingredient, which is more soluble than some dietary fi bers, is completely transparent in solution, maintaining the clarity and visual appeal of clear beverages.
Previous studies have also shown that in sugar-free beverages containing intense sweeteners, the addition of the ingredient as a fi ber source may improve the fl avor profi le of the drink. Samples had a more sugar-like fl avor and exhibited a mouthfeel closer to a sugar solution. Also, the ingredient masked off-tastes and aftertastes often attributed to intense sweeteners.
Sowing its Oats and Barley, Too
FDA’s heart-health claim for dietary soluble fi ber a few years ago not only played a major factor in helping to shape the future image of fi ber, but it also helped spawn or infl uence the development of a number of innovative oat-based ingredients.
Most recently, Nurture, Inc., Devon, Pa. (phone 610-989-0945, www.nurture-inc.com), received Frost & Sullivan’s Product Innovation Leadership of the Year Award for OatVantage, a 54% beta-glucan oat bran concentrate. The highly concentrated product makes possible a number of food categories to meet the requirements for the claim. The ingredient may be used in cereals, snacks, nutrition bars, dairy beverages, supplements, and other products without adversely affecting their taste and texture.
A broad range of high-fi ber oat bran and fl our products under the name Oatwell® is available from Oat Ingredients, LLC, Boulder, Colo. (phone 303-818-1117, www.oatingredients.com). The ingredients offer levels of oat soluble fi ber (beta-glucan) to 22% and total dietary fi ber to 44%.
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Canadian Harvest® Oat Fibers from SunOpta Ingredients, Bedford, Mass. (phone 800-353-6782, www.sunopta.com), provides food and beverage products better texture, longer shelf life, and higher processing yields while adding fi ber. The oat fi bers are each designed for a specifi c application, depending on their functionality. For example, one series of fi ber is highest in water and oil absorption and reduces breakage of fragile products such as taco shells, tortilla chips, and sugar cones. Another series, because of its whitest color and smooth mouthfeel, is more suited for breads, tortillas, and baked goods. Because it provides a coarser texture, a third series is more applicable for pasta, cereals, grain breads, and crackers.
Barley, too, is seeing its share of innovations. For example, a natural, waxy, hulless variety of barley, Sustagrain®, is reportedly the fi rst whole-grain product that is both naturally high in dietary fi ber and low in starch. Compared to other common cereal grains, it delivers two to three times more fi ber with approximately half the starch. Because of its unique carbohydrate composition, the whole-grain barley product is one of the lowest glycemic index grains commercially available. The product is part of the whole grains portfolio from ConAgra Food Ingredients, Omaha, Neb. (phone 402-595-4000, www.conagrafoodingredients.com).
Barley Beta Glucan, currently under development by Cargill, is a concentrated soluble fi ber derived from barley that has cholesterol-lowering properties similar to those of oats. The ingredient can add benefi cial fi ber to snacks while demonstrating optimal viscosity for such applications as bars, cereals, and beverages.
Adding Flavor to Herbal Teas
When you think about applications for roasted grain ingredients, herbal teas probably do not come to mind fi rst. Yet, roasted barley ingredients from Briess Malt & Ingredients Co., Chilton, Wis. (phone 920-849-7711, www.briess.com), can help manufacturers create fl avors in herbal teas.
Three types of Caramel Malted Barley add varying degrees of sweet caramel to burnt caramel flavor, while Specialty Roasted Barley Cracked contributes an intense roasted fl avor and color. While these grain-based ingredients are not being used to fortify herbal teas with fi ber, their associations with fi ber certainly causes the mind to refl ect on the possibilities of using fi ber-based ingredients to add levels of fl avors, fl avor notes, or sweetness to different applications. Also, the fact that the tea category has been experiencing rapid growth underscores the potential for fi ber in other products that are becoming increasingly popular.
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Maltodextrin Lowers Glycemic Index
A source of soluble dietary fiber, Fibersol-2 is a “digestion-resistant maltodextrin produced by treating corn starch with heat and enzymes. The ingredient, available from Matsutani America, Inc., Decatur, Ill. (phone 217-875-9819, www.MatsutaniAmerica.com), can help lower the glycemic index of such fi nished products as beverages, baked goods, dairy products, confections, and dietary supplements.
A spray-dried powder with a minimum of 90% soluble dietary fi ber, the ingredient demonstrates rapid dispersion, is clear or transparent in solution, and is stable under virtually all processing conditions. In addition, it has very low viscosity, is odorless and tasteless, and provides water-binding and improved body and texture.
Giving the Cranberry to Fiber
A new version of a sweetened dried cranberry contains half the sugar and twice the fi ber of the original product, while delivering the same processing tolerance, stability, and appearance. The product was launched at the FIE exhibition by the Ingredient Technology Group of Ocean Spray Cranberries, Inc., Lakeville, Mass. (phone 508-946-7606; www.oceansprayitg.com).
The product’s combination of complex carbohydrates, which act as a soluble fi ber source, reportedly lends sweetness and provides a balanced glycemic response. The versatile ingredient retains its shape and color throughout manufacture, and is suited to a wide range of applications, particularly baked goods, cereals, salad toppings, and trail mix.
This ingredient is another example of formulating foods that emphasize partnering higher levels of fi ber with lower levels of sugar—an effort aimed at lowering childhood and adult obesity levels. “Global consumer demand for low-sugar products is expected to double over the next two years,” said Arun Hiranandani, Senior Manager, Worldwide Marketing at Ocean Spray ITG. “These latest launches are an ideal way for food manufacturers to enter the fast-growing health food market, adding value through incorporating real fruit without boosting sugar quantities.”
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Combining Indulgence with Fiber
Consumers do not expect to derive the health benefi ts of fi ber in their favorite treats, partly because of fi ber’s traditional associations with health foods and partly because that component might compromise the eating qualities of their snack or dessert.
However, new eating opportunities for fi ber are being created. For example, a chocolate cookie made with an encapsulated fi ber provides sustained energy and other benefi ts of fi ber without compromising the taste or texture of the product. The prototype, which combines indulgence with the benefi ts of high fi ber, was developed by Kerry Ingredients, Beloit, Wis. (phone 608-363-1200, www.kerryamericas.com).
A serving of two cookies is said to meet the defi nition of a “good source of fi ber.” The fi ber is also working well with other ingredients in the cookie formulas, such as yogurt powder.
In addition to its encapsulated fi ber, the company also recently introduced its whole-grain soy fl our from its Nutriant business. Available in both full- and reduced-fat versions, the whole-grain fl our features 80% more dietary fi ber than whole wheat and can be used at inclusion levels that support “good source” or “excellent source” fi ber claims. In addition to its health values, the fl our delivers functionality and is supported with formulas in several application categories.
How Sweet Fiber Is!
An inulin/fructoligosaccharide product—a sweet liquid fi ber syrup called Frutalose L85—replaces sugar and sugar alcohols in nutrition bars and confections. Extracted from chicory root, the ingredient provides a number of functionality benefi ts, including pleasant sweetness, proper texture, humectancy, and fl avor enhancement.
The ingredient, which has 85% fi ber, 75% solids, and a low glycemic index, is produced by Sensus America, LLC, Monmouth Junction, N.J. (phone 646-452-6144, www.sensus.us). Using the ingredient, the company developed two nutrition-bar concepts—Fiber+ (high fi ber) and Sustenergy (low glycemic index).
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Healthcare Initiative Teaches About Fiber
A healthcare initiative which teaches consumers about making better food and lifestyle choices is being launched by GTC Nutrition, a business unit of Corn Products International Inc., Golden, Colo. (phone 800-522-4682, www.gtcnutrition.com). One of the advantages of such a program is that it will educate consumers about the advantages of different fi bers.
For example, a prebiotic soluble fi ber—NutraFlora® short-chain fructooligosac-charides—delivers superior mineral absorption, reinforced immunity, improved digestive function, and contribution to a healthy cholesterol metabolism. Its formulation benefi ts include superior stability, solubility, and dispersion; replacement of sugar and fat; and enhancement of fl avors.
Natureal™ oat bran is a soluble and insoluble oat fi ber that contains up to 20% oat beta-glucan for maintaining healthy cholesterol levels, preserving healthy blood sugar levels, and sustaining a feeling of satiety. The oat bran concentrate contributes to viscosity and texure and extends the shelf life of baked goods.
No One Perfect Fiber
As fi ber develops its new image, it becomes even more important not to see fi ber simply as fi ber—one size fi ts all—or for that matter, to expect the existence of a “Mega-Fiber” calling attention to itself. In fact, part of fi ber’s new image relies on its invisibility from a functionality standpoint—its ability not to affect the taste, texture, or appearance of the fi nished product.
Rather, for fi ber to maintain the image discussed in this article, we have to understand the differences between different fi bers, their properties, sources, and the potential health benefi ts they offer.
This understanding of fi ber is especially crucial when talking about functionality. Here I refer to an interesting quote by Jon Bodner, Senior Manager, Applications & Market Development, J. Rettenmaier USA, a major producer of refi ned insoluble dietary fi bers.
“After 20 years in the fi ber industry, I can safely say there is no perfect fi ber product,” Bodner notes. “There are products that are better suited to particular applications than others, and it is important that formulators realize even within the same substrate, there can be vast differences in fi ber characteristics.
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“A case in point would be insoluble oat fi ber. Currently on the market and even within our own product line, we have oat fi bers ranging from minimally processed, low-absorption options to highly extracted, high-absorption fi bers. While the inclusion of a 3% level of a highly extracted oat fi ber in an ice cream cone will impart additional strength, inclusion of a minimally extracted oat fi ber product might actually make the product weaker.”
Fortunately, as Bodner observes, through careful substrate and process selection it is possible for fi ber manufacturers to produce and offer a wide variety of fi bers to cover the vast array of applications in the marketplace. And what an extensive range that is: fi ber enrichment/caloric reduction, metabolizable-carbohydrate reduction, moisture control, anticaking properties, textural modifi cation, and structure enhancement. And, for you pet lovers out there, even pet food dental care!
Not too shabby for an ingredient once merely described as roughage.
What Is Dietary Fiber?
Inquisitive minds, especially lawmakers, want to know the answer to that problematic question.
In the U.S., there is currently no formal defi nition for dietary fi ber, although FDA is in the process of developing one. Dietary fi ber, which is required by the Nutrition Labeling and Education Act of 1990 to be listed on the nutrition label, has been defi ned by a number of analytical methods. And there lies the escalating confusion. Which comes fi rst: the methodology or the defi nition? The cart or the horse?
At an IFT Chicago Section meeting held on January 9, 2006, George C. Fahey Jr., Professor of Nutritional Sciences, University of Illinois, gave a presentation on the dietary reference intakes for fi ber. His report included a rationale for a formal defi nition of dietary fi ber.
As it stands now, compounds which have physiological fi ber-like benefi ts cannot be termed dietary fi ber because accepted AOAC methods do not analyze them as such, while compounds which have no physiological fi ber-like effects have been analyzed and termed as dietary fi ber. Fahey emphasized that a formal defi nition would determine the methodology; without a defi nition, the methodology determines what fi ber is and is not.
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In 2001, the American Association of Cereal Chemists (now AACC International) defi ned dietary fi ber as “the edible parts of plants or analogous carbohydrates that are resistant to digestion and absorption in the human small intestine with complete or partial fermentation in the large intestine. Dietary fi ber includes polysaccharides, oligosaccharides, lignin, and associated plant substances. Dietary fi bers promote benefi cial physiological effects, including laxation, and/or blood cholesterol attenuation, and/or blood glucose attenuation.”
There are also different types of fi ber.
Simply put, insoluble fi ber does not dissolve in water. It passes through the digestive system intact, facilitates passing food through the intestine, and increases fecal bulk. Soluble fi ber, on the other hand, dissolves in water and gels in the stomach, slowing the absorption of glucose into the blood stream. Soluble fi ber also affects cholesterol and glycemic reduction.
In addition to soluble and insoluble fi bers, there is also a growing interest in resistant starch. AACC noted that resistant starches require special consideration (see Cereal Foods World, March 2001). By defi nition, resistant starches escape digestion and absorption in the human small intestine, to be digested or fermented in the large intestine. This ability can provide benefi ts by reducing the caloric value of the food while providing energy to the bacteria of the colon, thus enhancing healthy fermentation there.
From a physiological (and benefi cial) perspective, it certainly sounds like resistant starches can be considered a fi ber. However, from an analytical perspective, it may not be that simple. If their resistance to digestion cannot be controlled in other than experimental situations, they cannot be labeled as or considered to be a dietary fi ber. Again, a clearer defi nition of fi ber could help solve this problem.
Today, there are several methods of analysis for the measurement of resistant starch. The AOAC-approved method for resistant starch, AOAC 2002.02, needs further comparisons to in-vivo measures for validation. AOAC-approved methods 985.29 and 991.43 have analyzed resistant starch as a dietary fi ber for food labeling purposes. However, measurements can be confounded by the fact that resistant starch levels may not be stable—they may decrease with cooking (gelatinization), then increase with cooling (retrogradation).
In 2002, the Food and Nutrition Board of the Institute of Medicine made a distinction between (a) dietary fi ber, “which consists of nondigestible carbohydrates and lignin that are intrinsic and intact in plants,” and (b) functional fi ber, “which consists of isolated, nondigestible carbohydrates that have benefi cial physiological effects in humans.” FNB defi ned “total fi ber” as the sum of dietary fi ber and functional fi ber.
Fahey described the distinguishing characteristics of dietary fi ber vs functional fi ber. With dietary fi ber, the plant cells and their three-dimensional interrelationship remain largely intact. Dietary fi ber comes only from plants, and their sources contain other macronutrients and micronutrients. Functional fi ber, on the other hand, may be isolated, extracted, or synthesized. It can be of animal origin, and it has to show a benefi cial physiological effect in humans.
If such a distinction is made, then education would be required to explain “dietary fi ber” and “functional fi ber.” Food databases, including the USDA food database, would have to be modifi ed. Functional fi bers would have to show a health benefi t to be on the food label. And new analytical procedures would be required for fi ber analysis.
But before any of these things can happen, a workable defi nition needs to be reached—a challenge which has existed since 1953 when nutritionist E.H. Hipley fi rst coined the term “dietary fi ber,” but one that continues to grow in importance, especially as consumers become more interested in whole grain foods, low-glycemic products, weight management, and an understanding of the benefi ts of “good carbs” in general.
Next month’s Ingredients section looks at new developments in the area of sweeteners and sweetener combinations.
by Donald E. Pszczola,
Senior Associate Editor