Tuesday, July 15, 2008

Bread Fortification on the Rise


Bread in its many forms and flavors has become a staple in countless cultures. It is believed that as far back as 15,000 B.C., nomadic hunter-gatherers discovered wheat was edible. Moistened grain meal formed pastes that, when “cooked” on heated rocks, yielded the first flatbreads. It was the Egyptians who first isolated yeast cultures to make breads rise. From Egypt to Greece to Rome, bread became more than a staple. The type of bread a person consumed was an indication of social status: the darker the bread, the lower the social station.

Enriching experiences

Through the years, grain millers found removing bran led to a more-desirable flour. Taste became milder and less susceptible to oxidation as rancidity-prone oils were no longer present. Removal of the grain’s bran and germ, however, left the flour short on naturally occurring vitamins, minerals and phytonutrients.

Bread’s relatively low cost and commonality to countless diet plans made it an excellent vehicle for nutrients missing from many consumers’ diets. Shortly after issuing its Recommended Daily Allowances (RDAs) in 1941, FDA was joined by bread manufacturer Continental Baking Co. in developing a bread-enrichment program, adding niacin, riboflavin (B2), thiamin (B1) and iron to bread to help stop the spread of nutritional-deficiency-related diseases, including beriberi, pellagra and severe nutritional anemia, in the United States. More recently, folic acid has become a common enrichment ingredient, helping prevent neural tube birth defects like spina bifida.

Because enriched bread is typically consumed as part of a greater meal item, its added vitamins and minerals are better absorbed. Calcium, for example, is more effectively absorbed in the presence of protein. Consuming calcium-fortified bread as a peanut butter or meat-and-cheese sandwich, therefore, improves the absorption of the added calcium.

Health-conscious consumers have discovered that bread provides nutrients their fast-paced diets fall short on. Unlike “enrichments,” where vitamins and minerals are added to enhance or replace naturally occurring elements, “fortification” programs add nutritive elements normally not present. It is these fortified products to which consumers are turning for help in their quest for better health.

Loaf legalese

Bread’s standard of identity (Title 21 of the Code of Federal Regulations, Section 136, Part 116), while established to protect consumers and manufacturers, can place constraints on developers seeking to improve or enhance bread products. Calcium salts, for example, are limited to a combined level of 0.25 parts per 100 parts of flour. Monocalcium phosphate (MCP) is one exception to the limit, and may be used up to 0.75 parts per 100 parts of flour (including any MCP present in the flour used). “Calcium phosphates provide multiple functional benefits in a single product,” says Barbara Heidolph, principal, ICL Performance Products LP, St. Louis. MCP added for dough conditioning also provides calcium fortification. “In standard bread products that use MCP, health claims cannot be made, because at a two-slice serving, you would get only 75 mg calcium per slice,” she says. “To make a ‘good source’ claim, you must have 100 mg per serving.” There are options, though, for the creatively named products. “In nonstandard bread, especially those formulated with healthful ingredients like fiber and whole grains, calcium phosphate can be used for fortification at levels to allow ‘good source of calcium’ or ‘excellent source of calcium’ claims,” she notes.

Fiber-rific flours

Americans’ underconsumption of fiber follows a general trend—replacing more whole foods with processed ones. But adding fiber to a formulation can affect several finished-product characteristics. Whole grains tend to create a denser finished product, a concern that can be addressed through leavening agents. Wheat supplies the gluten critical to dough development and structure, so fibers and grains other than wheat “dilute” the gluten content. Addition of vital wheat gluten can compensate somewhat for this. Adding these ingredients can also affect water absorption and mixing time, so product designers must be prepared to modify formulations and processes to achieve the desired loaf.

Whole grains can also affect color. Wheat and soy fibers can yield a yellow tone. Cellulose is one of the most white.

Flavor is yet another potential hurdle to clear. Wheat, barley and oat flours can impart strong flavors that could be undesirable in a bland-tasting product, but complementary in a multigrain formulation.

Fiber is a nondigestible complex carbohydrate, further defined by water solubility. Insoluble fibers, such as those mentioned above, pass through our bodies quickly, taking with it waste materials, helping reduce the risk of colon cancer. Bread applications typically utilize insoluble fibers, as they do not adversely affect mouthfeel, or fermentation and proofing processes.

Soluble fibers help lower glucose levels and cholesterol. They are obtained from fruits, vegetables and certain grains. Barley and oats, for example, contain beta glucans, nonstarch polysaccharides found to lower low-density lipoprotein (LDL, or “bad”) cholesterol. Since 1995, FDA has allowed foods containing 0.75 grams of soluble fiber from barley or oats to carry a health claim relating the consumption of beta glucan with reduced risk of coronary heart disease when the food is consumed as part of a diet low in saturated fat and cholesterol. Unlike insoluble fibers, though, soluble fiber can affect the viscosity, the amount of water required for proper processing, fermentation and proofing processes, and finished product texture.

It is important to note that while both oats and barley increase fiber in a formulation, neither can create yeast-risen breads on their own. Oats contain no gluten; barley has some gluten, but not enough to provide adequate rising.

Inulin is a soluble fiber composed of 2 to 60 fructose units. Shorter chains, 10 units and fewer, are referred to as fructooligosaccharides (FOS). In addition to boosting fiber content, inulin and FOS function as prebiotics (helping improve and sustain healthy intestinal microflora), improve calcium absorption and bone health, and help with weight control in adolescents.

“Typically, we recommend inulin for yeast-leavened systems,” says Joe O’Neill, executive vice president of sales and marketing, Beneo-Orafti, Morris Plains, NJ. “It has functional and cost benefits over oligofructose in yeast- raised and in leavened dough applications.” Another benefit of inulin is that it can be a used for additional fiber enrichment in high-fiber doughs with minimal water addition. Too much water addition in traditional high-fiber doughs can lead to microbial spoilage.

“Inulin has been successfully used in high-fiber dough systems without issues with dough handling or sticky doughs,” O’Neill notes. “Within the guidelines of ‘good source’ and ‘excellent source’ of fiber, inulin will have no effect on flavor or texture and can be used to make great-tasting, nutritious foods.”

Further, O’Neill says, growing recognition of inulin as one of the best and most-researched natural prebiotic fibers available is drawing developers to the claims they can make with inulin added to their products. “In addition to ‘good’ or ‘excellent’ fiber source, developers can also make structure/function claims based on inulin and oligofructose prebiotic function,” he notes. “Prebiotics are now taking fiber to a new level, allowing for claims on improved digestive health and function.”

Unseen heroes

Changing fiber content does not necessarily mean changing finished product characteristics. “Using certain ingredients, developers can boost fiber level invisibly, without negatively impacting the product,” says Doris Dougherty, senior food scientist, Tate & Lyle, Decatur, IL.

Resistant starch is one such group of ingredients. The term “resistant” refers to the starch’s ability to withstand human digestion. “While most starches are fully digestible, yielding 4 calories per gram,” notes Dougherty, “these are designed to be resistant to human enzymes, yielding 1.7 calories per gram (dry solids basis).” Tate & Lyle’s proprietary re-crystallization processing provides a physically modified (RS3) product that is more stable to heat and shear. But resistant starches are more than simple roughage. “These products have also been shown to act as a prebiotic fiber fermented in the colon, resulting in an increased amount of beneficial bacteria and short-chain fatty acids such as butyric,” she says.

Low water-holding capacity avoids stickiness, poor expansion and competition for moisture that could necessitate changes to formulation, processing time or temperature. As with any flour replacement, however, addition of vital wheat gluten may be necessary to ensure proper protein structure.

Invisible assistance can also be gained from soluble corn fiber. “It’s a fiber with sugar-like functionality,” says Dougherty. Unlike sugar, though, soluble corn fiber will not affect flavor or mouthfeel, she says.

The RS3 product is available in dry and liquid (70% fiber) forms, both of which exhibit solubility and stability unaffected by processing.

One if by land

Cultivated as far back as 3,000 B.C., flax is gaining attention as a healthful addition to modern bread formulations. Flaxseed is a powerful fiber-enriching material with approximately 28% dietary fiber composed of both soluble (one-third) and insoluble (two-thirds) fiber.

Flaxseed also has approximately 34% lipids, more than half of which is alpha-linolenic acid (ALA), an omega-3 fatty acid. Associated with a host of health benefits, omega-3s qualify for structure/function claims such as “omega-3 fatty acids support healthy brain function,” “omega-3s support cardiovascular health” or “omega-3 fatty acids support a healthy immune system.” Products that contain 260 mg of ALA per reference amount can be labeled as “high in ALA,” “rich in ALA” or “excellent source of ALA.”

Flaxseed is commonly used as intact whole seeds or ground seeds. Whole flaxseed can be utilized as a topping to improve appearance or texture. Poor adhesion can, however, leave many seeds in the bottom of a package. Direct addition of whole seeds, as in certain specialty artisan breads, requires a presoaking step to facilitate blending.

Shelled flaxseed can serve as an alternative to traditional whole flaxseed, notes Doreen VandenTillaart, vice president, sales and administration, Natunola Health Inc., Winchester, Ontario. “Whole flaxseed is not digestible in the human body due to the hard outer shell,” she says. “By removing this shell, the body can now break down the nutritional components in both the shell (fiber, lignans) and the inner kernel (omega-3).” Using a product with almost 31% ALA, developers can achieve a “rich source” claim adding less than 1% to their formulation. “With the shell removed, the seed is not as slick, having been opened up, and therefore has better sticking properties to dough, resulting in less waste,” she says.

Ground flaxseed is commonly used in American bread products. Milled flaxseed offers improved nutritional value and ease of addition over whole seeds. VandenTillaart notes that traditional milling processes can leave the ground material susceptible to oxidation. “When grinding flaxseed, the flax oil, which tends to be unstable, is pressed from the inner (yellow) flax kernel, resulting in rapid oxidation,” she says. “Shelling flax allows for the separation of the two flax components (the outer shell and the inner kernel), leaving the oil intact in the kernel and improving overall stability.” She suggests that oxidation often is to blame for the bitter notes imparted by ground-flax products. “Shelled flax,” she notes, “adds a pleasant, nutty flavor to foods.”

While flaxseed will act like many other whole grains, developers should consult with their suppliers for advice on formulation changes that might come from addition of a particular form and/or level of flaxseed. Additional fiber can necessitate additional water—as much as 75% of the flaxseed level. Maintaining existing proofing times and textures might require additional yeast. Gluten addition can also improve dough strength.

Two if by sea

Omega-3s are rising in popularly across the food spectrum, and breads are ripe for fortification with them. While flaxseed provides a rich source of one omega-3, certain oily fish deliver two others: eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). EPA and DHA are synthesized in the body from ALA, although the conversion rate is as low as 3%. FDA has approved EPA and DHA for qualified heart-health claims not allowed for ALA: “Supportive but not conclusive research shows that consumption of EPA and DHA omega-3 fatty acids may reduce the risk of coronary heart disease. One serving of [name of food] provides [x] grams of EPA and DHA omega-3 fatty acids. (See nutrition information for total fat, saturated fat and cholesterol content.)”

Fish-derived sources of EPA and DHA have one potential disadvantage: fishy taste or odor. However, microencapsulation technology has yielded EPA and DHA products that do not affect finished-product flavor or aroma.

Menhaden oil, lacking a strong fishy taste or odor, presents an opportunity for adding EPA and DHA to breads, according to the Menhaden Resource Council, Arlington, VA. Menhaden oil is FDA GRAS and certified for use in 32 food categories, including baked goods. However, sensitivity to heat can limit use of menhaden oil. Incorporation of menhaden oil into baked products should be done as late in the process as possible. Alone, menhaden oil is stable for up to 20 minutes at 350°F. Blending with a melted fat increases tolerance slightly, up to 40 minutes at 375°F, so it is suitable for bread.

Protein power

In 1999, FDA told consumers that daily consumption of 25 grams of soy protein would lower LDL cholesterol. Products containing 6.25 grams per serving could bear a heart-health claim. More recent studies have shown that isoflavones, phytochemicals in soy, might have positive effects on asthma, low bone mineral density, heart disease and cancer.

Beyond health benefits, soy offers functional benefits to bread formulations. Research performed at Texas A&M University indicates that water-binding, as much as 1.5 parts water to 1 part soy flour, can provide increased production volumes and improved shelf life. Soy can replace other allergens such as egg or nonfat dry milk and provide effective cost reduction. Soy flour’s enzymatic activity whitens a product with addition rates at or below 0.5%.

Part of what makes whole wheat nutritionally beneficial is the protein in the endosperm layer. “Using a proprietary method, one can isolate the precious aleurone layer where most of the desirable whole-wheat nutrients are concentrated,” says Kyle Marinkovich, marketing manager, Horizon Milling, Wayzata, MN. “Wheat aleurone brings consumers value by incorporating the nutritional benefits of whole grains while preserving the pleasing sensory qualities people enjoy in foods made from white flour: soft texture, high volume, mild taste and light color.”

According to Marinkovich, nutrition scientists have confirmed that isolated aleurone is preferable to full bran because it contains higher levels of almost all the whole-wheat nutrients believed to help promote better health: 45% dietary fiber; essential vitamins, including B6, niacin, and E; minerals such as potassium, magnesium, calcium, iron and zinc; most major antioxidants; and many phytochemicals, including tocopherols and tocotrienols.

The fiber, vitamins and minerals contributed by wheat aleurone will give rise to formulation or processing changes, as seen with any whole-grain or high-fiber ingredient, notes Rob Ostrander, technical services representative, Horizon Milling. “It may require additions of vital wheat gluten and dough conditioners to overcome the lower volumes and weaker tolerance to overmixing,” he says. “Most bakers will reduce mix and fermentation times to produce acceptable-volume breads.”

Wheat proteins provide additional solutions to challenges in yield and texture. “Loaf volume is dependent upon a strong gluten network,” notes Brook Carson, technical product manager, ADM Milling, Overland Park, KS. “As the gluten usage increases, the dough increases in elasticity and becomes difficult to process. Adding wheat protein isolate relaxes the dough, improving the process performance without negatively affecting the final-product quality. The final product has healthy whole grains, optimized texture and an increase in protein.

“Oftentimes,” Carson continues, “whole grains produce a more-dense texture and nutty flavor when compared to white pan breads. Wheat protein isolates not only improve the texture of the bread, but also mask the bitterness associated with whole grains.”

This just scratches the surface of the fortification options for your daily bread. No matter what the target loaf, dense and hearty or springy and soft, product designers can work with an array of ingredients to make bread healthier.

R. J. Foster is a wordsmith with a B.S. in food science from the University of Wisconsin-Madison and over 15 years of experience in the food industry. He can be reached through his website,wordsmithingbyfoster.com.

More Grist for the Bread Mill

Despite the USDA’s recognition that diets rich in dietary fiber promote healthy laxation and reduce the risks of coronary heart disease and type 2 diabetes, on average, consumers take in half of the recommended daily intake (RDI) of 25 grams per day (based on a target daily intake of 2,000 calories). To be labeled a “good source” of fiber, a product must contain at least 10% of the RDI (2.5 grams) per reference amount. An “excellent source” must contain 20% (5.0 grams) per reference amount.

A 100-gram portion of refined wheat flour contains 2.7 grams of fiber. Whole-grain wheat flour delivers 12.2 grams of fiber in the same 100-gram portion. Substituting one-third whole-grain white-wheat flour in a formulation can provide a means of increasing fiber. This substitution can, however, be made with a variety of flours. Buckwheat and corn flours have 10 grams of fiber per 100 grams, while barley flour yields 10.1 grams, oat flour 11.5 grams and rye 14.6 grams.

Best Bets for Bread Fortification

Results from the “2008 Food & Health Survey: Consumer Attitudes Toward Food Nutrition & Health” from the International Food Information Council (IFIC), Washington, D.C., indicate that two-thirds (67%) of Americans are making changes to improve the healthfulness of their diet. One of IFIC’s findings was that more than 80% of all Americans say they are currently consuming, or would be interested in consuming, specific foods or beverages for health benefits.

As the survey results demonstrate, some of the food components consumers are interested in are perfect fits for fortified breads. For example, when aware of the food component, 78% of consumers are trying to increase their consumption of whole grains. Similarly, 77% of consumers are trying to increase their consumption of fiber.

For complete survey results and analysis, see ific.org/research/foodandhealthsurvey.cfm.

1 comment:

Anonymous said...

How interesting. I didn't realize that bread could be fortified in so many ways. I read a book recently called "7 Steps to a Healthy Brain" by Dr. Paul Winner and some of these fortification ingrediants are recommended.