Whole grains: Making the conversion
September 13, 2016
by Laurie Gorton
Barley, an ancient grain with high levels of beta glucans, enhances the nutritional value of wraps.
Although Americans are getting better about eating their whole grains, they are still not getting enough to meet the 2015 Dietary Guidelines for Americans recommendations. Would they eat more if their favorite baked foods came in whole grain styles, too? It’s worth a try.
There is no doubt about the nutritional importance of whole grain foods. “We need to look at whole grain breads from scratch, not just as white bread with whole grains,” said Michael Beaven, PhD, director of technical services, bakery division, Watson, Inc. “Whole grains contain beneficial nutrients, but the nutrients generated from their metabolism in the lower gut — for example, the short-chain fatty acids — are at least as important and much better documented.”
From the baker’s perspective, whole wheat breads and rolls have always been part of their product offerings. Today, however, they work with a lot more grain types. “The industry wants to incorporate more grains,” observed Jennifer Tesch, chief marketing officer, Healthy Food Ingredients. “It has moved to a strong demand for ancient grains, many of which are gluten-free grains including quinoa, amaranth, sorghum, buckwheat and teff. There has been much focus on teff in the past six months due to its nutritional attributes.” Along the way, matters of taste and quality came into play.
So, the question becomes, how does the baker make the conversion? And the answer is, carefully.
Mind the performance
One thing that a decade of working with whole grain flours has taught bakers is the importance of water in successful products. These flours retain the bran and fiber components of the intact kernel, components that quickly tie up water that the starch and protein need, too. “The bran will suck up all the free water,” said Judie Giebel, technical services representative and AIB Certified Baker, Briess Malt & Ingredients. “The biggest factor is to get the hydration correct, and then the texture will come into perspective.”
Experience dictates an increase in ingredient water. “We’ve seen a lot of companies replace their basic white flour with whole white flour,” said Robert (Bob) Meyer Jr., director of technical services, Dakota Specialty Milling. “The challenges are that such products need more hydration and more strength.”
Good outcomes will depend on knowledge about how that water works in the dough. Different whole grains show different water-binding properties. “A great starting point for the developer is to understand the water-holding capacity, granulation and rate of hydration of the whole grain flour,” said Susan Kay, manager, product applications, Bay State Milling. “This information will help the developer optimize the water absorption in the formula.”
Differences between whole grain flours extend beyond hydration to affect performance as well. “A wise formulator will want to review all components of the baking process,” Ms. Kay continued. “Any whole grain flour addition will impact formulation, absorption, mix time, dough temperature, dough handling, pan-to-dough ratio, proofing, bake time and temperature, and cooling parameters.”
Qualitative analysis will give answers about the starch, fiber and protein content of the flour and whether the protein can form gluten and is of high or poor quality. Physical analysis will reveal its granulation. Such characteristics can be blurred or accentuated by the blend of grains chosen. Keep in mind that whole grain flour is generally heavier than conventional refined wheat flour.
“Some whole grain doughs act like putty, giving a ‘dead dough’ feeling,” Ms. Kay said. “They may lack elasticity and extensibility. Therefore, the dough may not tolerate harsh, high-speed or abusive handling processes. Modification to process may be required to ensure an attractive end product.”
Product volumes will likely be noticeably lower after proofing and baking than for baked foods made with conventional white refined flour. Ms. Kay recommended modifying the rate of inclusion of the whole grain flour, dough scaling weight, pan-to-dough ratio and dough strengthener addition as possible solutions to volume problems.
Perhaps the most noticeable changes involve color and flavor. “Whole grains can sometimes provide a darker color and a more earthy or hearty flavor profile,” said Zack Sanders, marketing director, Ardent Mills. “Some whole grains, such as sorghum, actually can provide a mild sweet undertone as well.” Whole wheat flour made from hard white winter wheat has almost no effect on either aspect. Compared with flours made from hard red winter wheat, the white wheat flour is perceived to be sweeter because it lacks the bran’s bitter red pigment.
Because whole grain meal and flour consist of the whole kernel, they tend to carry proportionally less starch — an important fact when producing extruded snacks. Fiber and protein become higher, thus diluting the starch, explained Todd Giesfeldt, mill R&D senior manager, Didion Milling. “Since starch is the main ingredient responsible for expansion properties during extrusion and puffing, this means there can be less expansion,” he said. If whole grain components are not thoroughly mixed or allowed to settle during storage, then excessive product variation can occur.
The higher fat content, too, can change the dynamics of extrusion by altering the friction between the dough and barrel, according to Mr. Giesfeldt. It will be harder to make whole grain snacks on single-screw extruders, which lack the positive pumping action of twin-screw systems. “For higher fat, you might need a new screw design with either type of extruder,” he added.
Chunjian (CJ) Lin, PhD, vice-president, R&D and QA, The Mennel Milling Co., summed up the challenges bakers face when converting to whole grain flours. “They report four common issues,” he said. “First is dough strength for bread. Because you add more matter — the bran and germ — the gluten has to do more. For cookies and crackers, you need to address water absorption and flavor. Whole grain flours affect the shape and size of these products; they bake up higher with smaller diameters.
“Second is flavor. Third is water absorption, and fourth is shelf life,” he continued. “By this, I mean aspects of flour inventory management.” Other than heat-treated flours, whole wheat flour is not stabilized, which leads to short shelf life and possible flavor problems. Also, whole grain flours may experience separation of the particulates.
Matt Gennrich works on a whole grain application in Cargill’s bakery lab.
Manage added ingredients
Real-world experience also finds other modifications are necessary when converting to whole grains. “When you go to 100% whole grain, or even 50%, there will be changes in ingredients and processing,” Mr. Meyer explained. “The dough will need more strengtheners. But if you want a clean label and if you want to retain texture, volume and shape and bake a healthier product, then you will need to use more enzyme products.”
Formulating advice often entails adding vital wheat gluten. During mixing, whole grain particles, regardless of their size, can tear the gluten naturally present, according to Matt Gennrich, research food technologist, Cargill. More gluten will be needed in the formula. “Similar conditions come with the use of whole grain corn and ancient grains,” he said. “They don’t contain gluten, so you’ll have to add even more.”
Of course, if you are adapting a corn-based formula to whole grain corn, gluten is not factor because the original product did not contain gluten to begin with, Mr. Giesfeldt observed. Granulation, however, is a different matter. “Bran in whole grain can produce a gritty taste if the particle size increases beyond 80 US mesh,” he said. “This can be a particular problem with whole grain corn meals and flour. Also, the whole grain can bring with it black or dark brown specs that may look like insect fragments to some consumers.”
If whole grain additions dilute the gluten too much, it will change the baking characteristics of the original white enriched flour formulation, Mr. Giesfeldt cautioned. “The situation is something like the gluten-free issue, where there is a need to compensate for the loss of vital gluten with alternatives like hydrocolloids and modified starches.”
Ingredients that add benefits can create processing problems. “One thing to remember is that these added grains, seeds, fibers, proteins and more do not provide any functionality in the baked goods,” Mr. Meyer said. They weigh down the structure and compete for water. “This especially can cause issues with the functionality of the enzyme-based blends being used for dough strengthening, oxidation and shelf life extension,” he noted.
The baker can get around such concerns, Mr. Meyer noted, in various ways. When using the sponge-and-dough method, the grains, seeds and fibers can be added at the sponge stage to allow pre-hydration. Or these ingredients can be soaked in advance and added at the dough stage. When using the no-time dough method, the baker will need to increase the amount of ingredient water.
Salt addition is a critical step. “Salt does have some effect on the development and strength of the gluten cell structure,” Mr. Meyer explained. “If you use a hold-salt method, consider more mix time on this step so the salt can help with this process.”
Because whole grain flours have more substance than refined white flour, they tend to yield heavier, thicker breads. Here, leavening can help. “When working with whole grain flours, it is important to adjust leavening and kneading time or stages, as needed, to produce a softer, lighter whole grain bread,” explained Johnnie Hadfield, marketing manager, Honeyville, Inc.
Not every ingredient change will be an addition; some might enable reductions. Such variations, described by Mr. Meyer, could include a cut in the formulation’s oil content because whole grain flour carries along all the natural oils present in the kernel. Or less salt might be needed since the grains are naturally more flavorful. “Sugar may also need adjusting,” he added. “And you may need a flavor addition to mask or complement the flavor.”
Because whole corn ingredients carry more proportionately more fat and less starch than conventional styles, snack processors will need to adjust settings on their extrusion systems.
Find the right format
Several new forms of whole grain ingredients help advance formulating for this category of baked foods. “A decade ago, wheat flour came in only a couple of different styles,” Mr. Gennrich said. “That was pretty much it. Now, we have flours made from white wheat, white spring, white winter and soft whole wheats, and a lot of other grains, too.”
Sprouted grain flours are the newest. In whole grain format, these flours may provide a flavor advantage. “Its extra sugars may mask some of the bitter flavor of the bran,” Mr. Gennrich said. “There has not been much research done on this matter, but sprouted flour is a hot button trend.”
He offered tips on using sprouted wheat flours. “[During sprouting,] some of the starches in the grain are converted to sugar,” he said. “You may need to adjust the process with dough strengtheners and may have to add more gluten.”
More formats are entering the market. Cracked, puffed and popped forms of whole grains deliver unique qualities to bakery applications. “Cracked grains such as barley can be used in topical blends to add dimension, color and texture to crumb coatings,” Mr. Sanders said. “Puffing or popping whole grains can also add a toasted/popcorn like flavor.”
Charlie Nave, director of baking quality, Grain Craft, suggested working with cracked wheat and wheat nuggets. “These offer a different texture in the finished product,” he said. “They are often presoaked prior to being added to the mixer. Again additional dough conditioner, strengtheners and vital wheat gluten may be needed in the formulation.”
Ancient grains now come in the form of crisps — Rice Krispy-like puffed particles. “They are a combination of a grain and a crisp,” Ms. Tesch explained. Such crisps are a natural for cereal bars, cereal clusters, granola and confectionery. The company also produces ancient grains in cracked, flaked, pregelatinized flours and grit formats.
Heat treating is now an option for whole grain flours, too. The result, according to Dr. Lin, is lower water absorption, better dough strength and improved shelf life compared with other whole wheats. “The heat treatment is applied to the bran and germ before it is recombined with the other mill streams that form whole wheat flour,” he said. The process also gets rid of unwanted enzyme activity by deactivating the lipase present. That improves the flour’s shelf life and performance.
Define goals early
When it comes to whole grains, the simple solution — a straight 1:1 substitution for conventional white flour — generally backfires in quality problems. There’s a better way to do it. “Oftentimes, the developer has certain requirements for success in mind as they relate to flavor, texture or visual appeal,” Ms. Kay said. “Defining ahead of time basic success criteria coupled with the physical/qualitative analysis will lead to a desired end product.”
Ms. Tesch added, “Formulating with whole grains will be much different in terms of texture, volume and other characteristics. As we work more with customers, we identify their requirements and then work together to guide them in their selection.”