Suddenly, gluten-free baked foods have gone mainstream. We’re talking wholesale-scale manufacturing. These foods are no longer just the output of small entrepreneurs and startups. Bimbo Bakeries USA, Flowers Foods’ Tasty Baking, Weston Foods, Barilla and Pillsbury recently jumped into the market. General Mills has been in for a while, and Udi’s has been there for many years. And that’s just the tip of the iceberg.

Worldwide, the gluten-free market is expected to be worth $6.2 billion in 2018, growing at a CAGR of 10.2%, according to MarketsandMarkets, a Dallas-based market research company and consulting firm. Bakery and confectionary (an international term that usually means sweet goods and pastries) will account for the largest volume share at about 46%, followed by snacks at 20%. In North America, 59% of the total market and the highest consumption are in conventional sales channels.

“Some consumers consider gluten-free to be a miracle food,” observed Andrea Caremoli, PhD, president and CEO, Caremoli USA, Inc., Ames, IA. “What’s driving it is that doctors are able to diagnose gluten intolerance quicker and more easily than in the past. And second, families with a gluten-intolerant member usually end up making one meal for the whole family. From a business perspective, if you have one individual forced into a gluten-free diet, you’ll change the whole family’s diet.” He also noted that many people follow gluten-free diets for presumed weight-control and health benefits.

This means big challenges for bakery and snack formulators. “First, you have to understand your target and what that market wants in addition to gluten-free: multigrain, low-protein, no-allergens and so forth,” said Rajen Mehta, PhD, senior director, specialty ingredients, Grain Millers, Inc., Eugene, OR. “And you need to start your formulation work with the grains.”

Constraints of working without gluten involve every part of the product chain, from ingredient supplier to bench to processing to distribution. “Once you get to full production, it’s important that gluten-free foods cannot be thought of in the traditional way,” said Kurt Becker, principal development scientist, ConAgra Mills, Omaha, NE. “Be open to new ideas, and don’t lose sight of what you are trying to achieve.”

Formula building 101

Without gluten, bread and other yeast-raised products would not be what they are. This native protein of wheat provides gas-holding functionality during makeup, structure after baking and protein to the consumer. Gluten is less essential to cookies and batter-based items, including cakes and muffins, but still has a role to play in their keeping quality and nutritional content.

The simplest advice is to start with the items that depend least on gluten. “Work first on cookie applications,” said William A. Atwell, PhD, retired Cargill researcher and consultant, Champlin, MN, who noted that the company started its gluten-free project in 2007. His group divided potential applications by increasing degree of difficulty: cookies first, batter-based items such as muffins and cakes next and bread categories last. “Bread is the most difficult case,” he said.

“The function of gluten is very different in each,” noted Dr. Atwell’s colleague, Jeff Casper, R&D manager of Horizon Milling, Wayzata, MN. “In cookies, you can swap out sources of structure by creating a composite flour.”

Dr. Atwell continued, “Batter-based items will need some added functionality to substitute for gluten. The big problems are with bread. It’s a learn-as-you-go situation.”

“The more you understand gluten, the more you can strategize to replace it,” Mr. Casper said. “It gets down to rheology and, specifically, how to create a strain-hardening material that replaces gluten.” (Strain hardening, a rheological term, describes what happens when the heat of the oven denatures protein to set the structure of the finished product.)

Cookies, crackers and other sheeted items will be easier to convert to gluten-free than breads, advised Dilek Uzunalioglu, PhD, senior associate, bakery and snack team leader, global applications, Ingredion, Inc., Westchester, IL. “Cakes are much the same,” she said. “For gluten-free bread, you will need a different system to achieve the final rheology that’s important to bread. But we approach each application differently.”

Replacing mixing functions

Just as gluten plays diverse roles in different products, it does so at various stages of production, too. “From a formulation standpoint, there is no single solution for replacing gluten,” explained Bryan Scherer, director of R&D, Penford Food Ingredient Co., Centennial, CO. “Gluten has different functions in raw products such as bread dough versus the finished baked product.” This requires understanding how to combine different ingredients such as starch, gums, proteins and gluten-free flours to compensate for functionality ordinarily supplied by gluten.

Initial results can be products with very different handling characteristics and equipment requirements than the full-gluten version, Mr. Scherer observed. “For example, gluten-free bread dough may not look or handle anything like regular bread dough and can require alternative mixing, depositing and forming equipment,” he noted.

Taking the gluten-free route generally starts with replacing wheat flour. “But you have to work with the whole formula,” Dr. Mehta said. “Starch is the next key. Then come the gums to add structure, and fiber allows fine-tuning of the texture, along with humectancy. Together, this is the challenge that gluten-free presents.”

Addition of starches, hydrocolloids, functional proteins, gluten-free grains and seeds adds to the functionality of the system, according to Colleen Zammer, director of product marketing, Bay State Milling Co., Quincy, MA. “Each of these ingredients has functionality in the various stages of baking,” she said. “Some are more useful to aid in water absorption and formation of a dough and others in structure, strength and gas retention.”

Nutritional improvement

The nutritional value of gluten-free items, criticized in the past, is on the upswing. Cheryl Borders, ADM research manager, soy foods applications technical service, Edible Beans, ADM, Decatur, IL, explained, “Gluten-free products are often made using refined flours and starches such as rice, tapioca, potato and corn. These ingredients are often lower in protein and fiber, so the addition of nonwheat sources such as soy proteins or edible bean powders can help improve the nutritional profile of the finished product.”

Legumes — peas, lentils and beans — get high marks for their protein content. “Lentils and chickpeas are extremely useful for this category,” Dr. Caremoli said. “They allow combination of gluten-free with a good amino acid profile.”

Seeds, too, play a big role in boosting nutritional content and offer unique textures, Ms. Zammer explained. “Seeds like chia and flax not only offer omega-3 fatty acids, fiber and protein but also can actually help boost functionality with their natural hydrocolloidal properties,” she observed. “Our sensory team has found that various blends of gluten-free grains and seeds can produce a well-rounded flavor profile that offers the gluten-free consumer variety.”

Consider flaxseed, a source of omega-3 ALA fatty acid. “A unique property of flaxseed is its gum mucilage, which helps baked goods retain moisture and overall structural integrity,” said Marilyn Stieve, business development manager, flax, Glanbia Nutritionals, Fitchburg, WI. It is available in a range of processed ingredients that also optimize shelf life.

And flax’s flavor is desirable, too. The company’s flaxseed-based hydrocolloid ingredients “have a nice wheat-like flavor profile that can help bring back some of the flavor notes that are typically missing in gluten-free formulations,” Ms. Stieve observed.

Going the whole way

Replacing wheat flour usually means working with flour milled from a different cereal grain. Two, in particular, are getting a lot of buzz lately: sorghum and corn.

“Sorghum is a good fit in many grain-based applications,” said Brook Carson, director of R&D, ADM Milling, Overland Park, KS. In extruded snacks and cereals, it has a clean flavor profile and a crisp texture without being too fragile. In baked foods, it provides protein and fiber at twice the level of brown rice flour. “Whole grain sorghum flour offers an important gluten-free solution that is more economical than specialty starches and competitively priced with other flours,” she noted.

Going beyond traditional cornbread and corn muffins, formulators are also looking more closely at corn for products such as cakes, pancakes and pie crusts. Todd Giesfeldt, R&D mill product manager, Didion Milling, Johnson Creek, WI, described corn as label-friendly and available at a good value. “Corn has its place in gluten-free formulas, as long as it’s formulated correctly,” he said. “It brings a flavor and texture that consumers will find pleasing.”

He noted that viscosity-controlled corn flour works well in kneading and automated dough processing equipment. In pregelatinized form, it provides stabilizing functionality. Corn bran brings fiber to the label and aids moisture retention with its high water-binding capacity.

“When you formulate with corn, you’ll have a lower protein level than with wheat,” Mr. Giesfeldt said. “Make sure the protein level is balanced correctly. It works well to mix corn with grains of higher protein.”

Particularly interesting is a new crimson red corn flour, according to Tara Froemming in business development with SK Food International, Fargo, ND. “It is naturally gluten-free and maintains its natural red color through processing and baking stages,” she said. “No additional color need be added, so it contributes to clean labeling.”

Quinoa, one of the darlings among ancient grains, carries desirable protein levels and represents a new stage in ingredients, according to Jeffrey Barnes, founder and owner, Edison Grainery, Oakland, CA. He described brown rice and tapioca flours as Mach 1 in gluten-free formulating. “Now, we’re seeing exciting new choices, bean flour, for example, and a new pregelatinized quinoa flour. Gluten-free products usually need starch to provide binding. That’s what makes the pregelatinized quinoa so interesting.”

More than one function

Gluten of the sort implicated in celiac disease and gluten intolerance occurs in wheat, rye and barley. But that leaves a host of other cereal grains to choose from. Ms. Zammer described sorghum, millet, quinoa, amaranth and buckwheat flours as advantageous in boosting the functionality, flavor and texture of gluten-free formulas. “They offer water-holding ability, whole grain nutrition and unique flavors,” she said.

Such experience with gluten-free whole grains confirms the need for a multi-ingredient approach. “It often takes a combination of several ingredients to replace the key functional characteristic that traditionally is provided by wheat gluten’s interaction with other ingredients in the process, often with repeated experimentation,” said Ning-Hong Li, food scientist, ConAgra Mills, citing xanthan gum and egg whites as good starting points.

Specifically, nonwheat flours require the formulator to replace gluten’s film-forming and gas-holding capacities by using a combination of cereal grains, gums, pectin and/or bran. Cereal grains that work in gluten-free foods include rice, sorghum, millet, amaranth and corn, “wherever you can find polysaccharides in a cereal grain without the presence of gluten,” Mr. Giesfeldt noted.

“When you bring in the right amount of protein, carbs, starch such as corn or tapioca and additives such as gums or pectin, you come up with something similar to what you get with wheat gluten,” Mr. Giesfeldt said. “You can use different types of bran such as corn bran or rice bran to help manage water.” Select finely ground materials, he cautioned, because at particulate sizes greater than 80-mesh, bran makes its presence known in the finished product’s mouthfeel.

Two more ingredients warrant consideration for their functional qualities, too. “Inulin can be critical to quality,” Mr. Casper said. Rich in soluble fiber, inulin supplements the fiber content of anything to which it is added. “Inulin has the benefit of being multifunctional,” he continued. “It plasticizes the batter, softens the crumb and contributes to finer grain in breads.” He described maltodextrin as having similar crumb-quality improvement properties.

Conventional baked foods depend on both their protein and starch components for their final structure, texture and eating quality. In the absence of gluten, much more of those tasks fall to the formula’s starches, both those native to the gluten-free flour itself and those added on their own merits.

“The use of the right starches and flours as bulk flour replacements are critical,” Dr. Uzunalioglu observed. Ingredion developed bulk flour replacers that act as the backbone of the formula by providing body, improved dough handling and finished texture. The starch side of the equation, she noted, improves dough handling, final product texture and increased shelf life. “Gums and non-gluten proteins are also used in formulations to help with dough handling, color development and texture,” she said.

Tapioca, potato and rice starches have long been staples of the gluten-free formulator. “You can use either cook-up or pregelatinized starches,” Mr. Casper said. “There are many kinds, and they have an impact on costs.”

Customized blends go a long way to maximize their usefulness. “Each starch provides specific functionalities, which can include viscosity, structure, moisture retention and elasticity,” Mr. Scherer said.

Care must also be taken with the choice of hydrocolloids such as xanthan, locust bean and guar. Some, as Mr. Casper noted, are subject to regulatory limits. “You’re going after certain rheological properties,” he said, “but you have to know which material to use and what regulatory issues it raises.”

Why so difficult?

Hands down, texture is the most difficult hurdle for gluten-free products. “It can be a challenge to mimic the texture of a traditional product made with gluten to meet consumer expectations,” Ms. Borders said.

Gluten does a superb job of structuring baked foods. The formulator needs to find a way to develop a gluten-like matrix in the dough that will retain gas during baking, explained Yoshi Mochizuki, director of product development, PGP International, Woodland, CA. This is what sustains crust and crumb structure after baking, he said.

It’s no surprise that the chief problem in gluten-free formulating is finding a functional substitute for gluten. The most difficult problem to navigate, according to Ms. Froemming, is finding a viable alternative to gluten and then sourcing it. “These materials must have the right formulation and functionality.

“Also, the user must understand what qualifies as gluten-free,” she continued. Ingredients must allow the baker to get below the 20-ppm-per-kg labeling threshold just announced by the Food and Drug Administration.

Gluten-free products are formulations, rather than recipes, Mr. Scherer cautioned. “This means carefully controlling ingredient quantities and ratios and placing tighter process controls over operations such as ingredient addition order, mixing conditions, proofing, etc.,” he said. “The second challenge is that gluten-free products may have very different rheology, handling characteristics and equipment requirements.”

For example, a gluten-free dough may appear too loose or runny, prompting the baker to try to “fix” it. But this is typical for a high-quality gluten-free bread, he explained. The third major challenge is to avoid cross contamination of the product if you manufacture gluten-free products in a facility that normally handles wheat or other gluten ingredients.

Achieving the lightness, softness and crumb resiliency is problematic, according to Mr. Becker. “Additionally, maintaining the softness and moistness of gluten-free baked items over several days is more difficult than for traditional wheat-flour-based products,” he said.

Particle size plays an essential role in organoleptic quality. “That’s where our approach of ‘grinding things fine’ comes in,” Dr. Mehta explained. “With grains like sorghum, rice and so forth, if you don’t grind them fine enough, they can destroy the structure of the dough. You have to grind finely, and on occasion precook, especially some of the ancient grains.”

Texture plays out in different ways. “Corn has a short texture,” Mr. Giesfeldt said. “If all you’re using is corn flour in a recipe, the results will be crumbly because of the protein form. It will act more like cornbread.”

And then there’s the matter of taste. “You have to be careful that the taste attributes fit what you are looking for,” Mr. Giesfeldt said. “You don’t want the corn flavor to be too strong in the blend. It works well to use multiple grains, so the corn brings sweetness and a nutty flavor without being overpowering.”

What’s the most difficult product to make gluten-free? For Dr. Atwell, it’s a toss-up between bagels and soft pretzels. “These products depend on gluten for their desirable chewiness,” he said. “They need a good bite.”

Looking at what’s next

The formulating experts Baking & Snack consulted for this article urged bakery formulators to “lean on the expertise of your suppliers” for help with this demanding category. “We have a bakery applications team that spends much time on gluten-free products,” noted Patrick O’Brien, bakery marketing manager, Ingredion. “And that includes attending plant trials.”

One additional thought: The formulator’s most useful tools will be strong powers of observation and creativity. End-product quality can redefine the entire process. “Keep an open mind,” Ms. Li urged.