Gluten-Free Formulation
July 11, 2006
Photo: Corn Products International |
Those with gluten intolerance and/or celiac disease have faced many challenges in their quest to follow a gluten-free lifestyle. First, these consumers tried many old-school “gluten-free” breads, cereals or cookies and were turned off by poor taste and texture. Then they realized that gluten, for all intents and purposes, appears inescapable in processed foods.
Something as innocuous as modified food starch could be made from wheat. Artificial flavoring might contain barley malt, another ingredient non grata. Soy sauce, beer, oat-derived vegetable gums: each might bear gluten’s taint.
These consumers have been stymied by the difficulties of being gluten-free in a gluten-friendly world. Talk to any celiac who’s scoured labels in search of stealth glutens or swallowed another dry, mealy gluten-free cookie, and you’ll understand why celiacs are a block with a bone to pick.
Whereas experts once pegged the number of Americans with celiac disease (also called celiac sprue) at one in 10,000, an epidemiological screening of more than 13,000 people in 23 states recalibrated that estimate to approximately one in every 133 people—about 3 million, or a bit below 1% of the population, according to the 2004 National Institutes of Health Consensus Development Conference Statement on Celiac Disease. Even that may lowball the figure, as a legion of undiagnosed “silent celiacs” could raise the count to one case in every 83 Americans.
In fact, celiac disease, in the words of gastroenterologist Dr. C. Robert Dahl, is “one of the great mimics in gastroenterology,” so it is notorious for outwitting its sufferers and their physicians.
Cynthia Cooper, a registered dietitian and executive director of the Gluten-Free Certification Organization, Seattle, agrees. “It can look like Crohn’s disease. It can look like colitis. It can look like irritable bowel syndrome. It can look like so many things that physicians aren’t used to looking for. And oftentimes, when they can’t find something related to a GI problem, they simply write it off as irritable bowel syndrome and forget that it could be celiac disease, because they’ve been taught that it’s very rare. But it’s not. It’s just under-diagnosed.”
The matter with gluten
Misunderstandings persist, such as the belief that celiac disease is tantamount to a common wheat allergy. But while immunoglobulin-E reacts to wheat’s albumin and globulin proteins in that allergy, celiac disease involves the body’s T-cell response to gluten. More importantly, wheat’s gluten isn’t the only one to which celiacs respond. “Gluten” generally signifies a complex of prolamin proteins called gliadins, and glutelin proteins called glutenins. This wheat-gluten complex contributes cohesiveness and structure to bread, trapping carbon dioxide in a protein scaffolding that solidifies in an oven’s heat.
With respect to celiac disease, gluten comprises a class of storage proteins found in all grains. The prolamin in rice is oryzenin; in corn, it’s zein. Barley’s prolamin is hordein, oat’s avenin, and rye’s secalin. While each gluten’s precise amino acid sequences differs, they share key traits— the most relevant to the celiac being that those found in wheat, barley, rye and, in some cases, oats trigger an autoimmune response. (See the sidebar “Feeling Your Oats?” for more about oats and celiac disease.)
Living gluten-free
Fortunately for the celiac, halting future damage and healing what’s already been done is a DIY affair: no pills, no surgery; just the removal of wheat (including semolina, spelt and triticale), barley, rye and oat glutens from the diet. While elementary in theory, it can be anything but in practice.
For starters, the world has yet to define a universal “gluten-free” standard. For international trade purposes, the Codex Alimentarius Commission, a joint effort of the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) Committee on Nutrition and Foods for Special Dietary Uses, declares that no more than 0.03% of a gluten-free food’s total protein can come from wheat, barley, rye or oats. Codex is in the midst of revising this standard —and unable to reach a consensus in doing so—but until it does, it sets its limit at no more than 20 ppm (20 mg/kg) gluten in a naturally gluten-free product, and no more than 200 ppm (200 mg/kg) in a product “rendered gluten-free in processing” (such as purified wheat starch or alcohol distilled from rye or wheat).
FDA hasn’t signed on to this standard. “So, officially in the U.S.,” Cooper says, “there is no definition of glutenfree.” Here, gluten-free has come casually to mean wheat-free, owing largely to the assumption that “the definition of ‘gluten’ means wheat, and ‘free’ means zero,” she explains. Of course, this is a disaster in the making for a celiac intolerant to barley, rye and oats, as well as wheat, and FDA acknowledges that the situation needs to be rectified. It made a start by including gluten with other major allergens in the ingredient disclosure requirements of the 2004 Food Allergen Labeling and Consumer Protection Act (FALCPA), and has also charged itself with defining “glutenfree” for labeling purposes by 2008.
Obviously, those standards are needed to meet the growing demand for gluten-free products. In the first 10 months of 2005, 691 new gluten-free items came to market, raking in $349 million over the 52 weeks ending Nov. 5—a 14% jump above the previous year, according to market research firm SPINS, San Francisco. Mintel International Menu Insights Group rates gluten-free among the top-10 most-prominent health declarations on restaurant menus, and Whole Foods and Wal-Mart have cast their lot with the category, establishing entire sections dedicated to gluten-free goods.
Gluten’s good graces
Mary Schluckebier, executive director of the Celiac Sprue Association (CSA), Omaha, NE, notes, “When I became a celiac, I started working on making foods that would taste good. And I can make the fluffiest cinnamon rolls that anybody’s every tasted. But it takes a very long time, so I don’t do it very often. Most people who are being diagnosed as celiac now do not want to cook unless they can just throw something in the bread machine or the casserole.”
Despite the more than 2,000 gluten-free products gracing supermarket shelves, consumers can be forgiven for wanting more—or at least better— products. Because the central dilemma for the celiac is finding products that satisfy the senses without causing sickness, the central dilemma for the manufacturer becomes eliminating gluten without compromising a product’s sensory qualities.
Despite being literally toxic to celiacs, gluten also functions indispensably in many of their favorite foods. Says Bill Atwell, research fellow and manager, bakery technology, Cargill, Inc., Minnetonka, MN, “Gluten is an extremely functional ingredient. And on top of that, it’s a very unique ingredient.”
This is particularly the case with wheat gluten, whose elasticity, cohesiveness and heat-set skeleton make our very concept of bread possible. That’s why traditional, yeast-leavened breads— “light, airy structures where you need something to retain the gas and something to set the structure in the expanded form,” Atwell says—put up the biggest fight against gluten-free formulation.
Lacking a protein framework, gluten-free breads “are typically very dense,” says Eric Shinsato, technical sales support manager, Corn Products U.S., Westchester, IL. “You don’t get that same cell-structure development that you do in wheat bread because, whereas the wheat gluten helps hold the gas in, other grain proteins don’t do that.” Another drawback he’s noted is the infamous dryness and tendency to crumble of gluten-free baked goods.
“One of the things that we have found, talking to consumers, is that they can’t make a good sandwich because the bread just falls apart,” he says. (Not surprisingly, breads and baked goods generate the second-lowest sales of any gluten-free product category.) Cookies, brownies, pie crusts and even dense quick breads suffer less from a gluten-free makeover. But even they need something to hold them together and, historically, gluten has been the tie that binds. In gluten-free cookies, Shinsato says, “Most of the products that are on the market now tend to be on the dry side and, in turn, are kind of crumbly, too.” As for pie crusts, while the high proportion of fat to flour somewhat attenuates gluten’s influence, Atwell notes “people like the flakiness in pie crusts, and the gluten does play a bit of a role in defining the cereal layer in that flaky structure.”
Noodles and pasta also rely on gluten’s “glue” to keep them from falling apart, either before or after cooking. Asian cultures may have been making noodles from rice and soy flours for centuries, but, says Janet Carver, culinary group leader, National Starch Food Innovation, Bridgewater, NJ, “They have a very different bite quality and cooked quality.”
Get the gluten out
No matter how functional, glutenfree manufacturers have no choice but to get rid of the gluten. In its place, they’ve turned to naturally gluten-free starches and flours made from rice, tapioca, potato, arrowroot, nuts and legumes. However, these alternatives often create as many problems as they solve. Notes Carver, “Unfortunately, many of the ingredients used to achieve a gluten-free product have very different flavor and eating qualities. Some of the replacement starches or flours can be very high in viscosity and exhibit very cohesive texture when being cooked, too.”
Protein content may be their most fundamental drawback. According to Shinsato, a flour’s protein level should hover around the 10% that’s typical in wheat flour, plus or minus a few points, depending on whether we’re making bread, pastry or pasta. “Other flours out there don’t have that high of a protein content,” he continues, with most alternatives topping out at about 5%. “Rice flour does work,” he notes, but at a bit below 6% protein, “it’s still pretty low.” Plus, the more you use—and with the low protein, you need more—the grittier it makes the finished product.
Manufacturers must also consider how alternative flours affect product flavor. Rice’s blandness partially makes up for its grit factor and low protein. But corn, soy and even potato flours come off much more assertively and are hard not to recognize —not a good trait in a baked good trying to pass for wheat. The upshot for manufacturers, Atwell says, is that “they get something where the texture’s already off, and then they’ve got a flavor problem because they’ve brought in something that’s not native to a bread formula. And when they put things in to try to reduce some of the flavor issues, in many cases they actually end up complicating the flavor profile even more.”
Stealth glutens
Fortunately, not all gluten-free revamps are so confounding. Getting rid of “stealth” glutens—those in flavor carriers, binders, fillers and emulsifiers and used in everything from salad dressings to self-basting turkeys—is a reformulation giveaway compared to baked goods.
Says Atwell, “Gluten and the related proteins are used widely in the food industry in lots of places where you wouldn’t even think they would be.” Chewing gum, for example, receives a dusting of wheat starch, and crisped-rice cereal may contain a gluten-containing binder. Shoyu-style soy sauce is made with wheat as well as soy, and gravy and sauce bases, Carver adds, “typically use autolyzed wheat gluten in their formulations, or may even contain flour.” Barley enzymes participate in the production of some rice-based beverages, and even mono- and diglycerides might be associated with a wheat-based carrier. True, the quantity of gluten that these ingredients contribute can be vanishingly small, but that’s all it takes for some celiacs to leave a product on the shelf.
Eliminating these glutens proves less painful because their presence is often just an accident of formulation, a consequence of cost, habit or their coincidental association with other ingredients. As a result, their role in the finished product —assuming they have one—is almost always readily replaced, making the reformulation object less the restoration of lost function than simply the identification of the gluten sources.
Plus, subbing out a wheat or barley ingredient might actually improve product performance. Notes Terry Van Winkle, vice president, sales, TIC Gums, Inc., Belcamp, MD, “If you look at products like soups or sauces or salad dressings that would normally contain flour or starch as a thickening agent, there are a number of alternatives you can design as replacement systems, depending on the texture and rheology you want and a number of other factors.” Of these, gums and gluten-free modified starch systems top the list. While they may cost more, their functionality makes them the better value in the end.
By gum!
The latest starch and gum technologies really come into their own when they can flaunt their functional prowess over traditional gluten-free ingredient options in baked goods, noodles, batters and breadings. Gums, for example, retain moisture, control water, entrap air, thicken, suspend and form films—all functions that would otherwise be missing or weakened in gluten-free foods. Van Winkle adds, “If you have other proteins in a formula —soy, for instance—gums will help stabilize the proteins while also reducing the tendency for amylase to retrograde, helping to lengthen shelf life not only by holding moisture but by lowering the staling rate.”
This is a boon to gluten-free breads, where a combination of xanthan with locust bean and guar can do worlds of good. What makes xanthan such a wise choice, Van Winkle says, is its heat tolerance during the baking process. “As you bake the bread,” he explains, “your internal temperature is going to be something under 200°F; xanthan will maintain its viscosity, and therefore its ability to hold a foam or a structure during that process.” Systems combining xanthan and locust bean gum also form gels as they cool, crosslinking to produce a polymer gel that reinforces the loaf’s structure.
In gluten-free batters and breadings, gum choice depends on the function it’s replacing. “If you’re making a batter that you want to expand, like a pancake batter,” Van Winkle says, “one of the thickening gums, like a xanthan or a CMC (carboxymethylcellulose), or even guar to some extent,” will come in handy. Coating batters, on the other hand, need sound adhesion, suggesting a gum with a firmer tack, like gum arabic. And, adds Carver, “Batters can use combinations of corn starches and dextrins for extra crispness.”
Starchy solutions
Even at the 1% to 2% levels common to breads, batters and baked goods, gums still exact enough of a price premium to encourage manufacturers to reduce their presence as much as possible—a goal they can achieve by pairing a gum with a modified gluten-free starch.
Shinsato’s company promotes a modified tapioca starch as a gum-sparing starch that also delivers “a lot of the benefits you see when you’re using wheat flour,” he says. “It’s unique in terms of how it reacts in baked items. It actually enhances expansion properties of the product, so if you’re looking at bread, you get a lot of volume in the loaf. You get aeration of the structure—much more than what you see in the other glutenfree products, which are very dense. It gives you better water-holding ability, so you get better storage stability of the finished product, whether it’s refrigerated or frozen.”
Able to replace most of the flour in a baked-good formula, it might appear in a typical loaf of bread at 30% on a total-weight basis, with rice flour making up another 20%. “Even in our pizza crust, we’re looking at close to 25%,” Shinsato says, with rice flour making up “a little bit less than 20%.” Shinsato says, “One thing we had to do was throw everything we knew about wheat-based products out the window because with gluten-free, it doesn’t apply. We were doing things to create a totally different animal from the traditional wheat-containing product.”
That’s just what it may take—a sort of food “Manhattan project”—to improve significantly the lot of gluten-free foods. “We need to attack this as a big problem and it needs to be understood and it needs to be solved,” says Atwell. “What is this gluten polymer all about? How functional is it? We need to go back and review all that and then figure out what kinds of things we can come up with that are similar to gluten and are food-approved and don’t elicit any other allergic responses, and then build the baking systems around those fundamental polymers and ingredients. And I think that’s the long-term approach that would eventually give consumers who need to have this kind of product something that’s of better quality.”
Kimberly J. Decker, a California-based technical writer, has a B.S. in Consumer Food Science with a minor in English from the University of California, Davis. She lives in the San Francisco Bay area, where she enjoys eating and writing about food. Contact her at [email protected].
Feeling Your Oats?
Whether experts are debating the best assay for measuring glutens, the quantities sufficient to trigger a celiac response, or the simple identification of just which foods contain the pesky proteins, reaching a consensus is like chasing the end of a rainbow.
Just ask anyone who’s tried to puzzle out oats’ status in a gluten-free diet. Notes Cynthia Cooper, R.D., executive director of the Gluten-Free Certification Organization, Seattle, “The initial thought was that oats had the same amino acid sequence that we know causes the damage that celiacs get from wheat. But through grain analysis, we can see that the amino acid sequences are not the same.” With only 10% to 15% of their total protein present as prolamins—the fraction most associated with triggering a response—oats just might pose no harm when eaten in moderation, say several studies. E.K. Janatuinen and colleagues, for instance, are responsible for conducting three such studies—one of which lasted five years—and they found that most subjects easily tolerated 50 to 70 grams of oats per day.
But, as in all controversies, a dissenting camp is quick to prove otherwise. In their respective studies, H. Arentz-Hansen et al. and K.E. Lundin et al. both found that 50 grams of oats per day could elicit a response in sensitive celiacs, even when investigators screened the oats for contamination from wheat, barley or rye glutens.
So, Cooper says, “If there’s a problem, now the thought is that it could be one of two things: It could either be that the cross-contamination level is high enough to cause people to react,” or “there may be some people who have an allergic-type reaction to oats.”
Not content with the ambiguity, many celiacs and their advocates, such as the Celiac Sprue Association, Omaha, NE, advocate—provisionally, at least—a when-in-doubt- keep-it-out approach to oats. Says Cooper, “For right now, we do classify oats as a high-risk ingredient.” Until the experts settle it once and for all, that seems the least controversial road to take.
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