R&D / Fibers, Flours, Grains / Gluten Free

Information On Legume Flour

Between the interest in fiber and allergies such as celiac disease, it’s time to spill the beans about these specialty flours.

By Frances Katz, Senior Technical Editor

Beans as an ingredient meant soybeans a decade ago. Soy flour, meal, isolate — these ingredients usually were chosen for the protein they added. But between the small boost given legumes of all types by the new Dietary Guidelines for Americans and consumers’ growing appetite to try new things, beans of all varieties may be poised for a renaissance.

Dietary fiber is very much in the nutrition news these days. Fiber has been identified as one of the biggest deficiencies in the American diet, and dry beans and peas are the best sources of fiber, the USDA says. They also contain significant amounts of other nutrients Americans are not getting enough of – magnesium, iron, zinc and folate – and are high in protein.

In the original Dietary Guidelines, released in January, “legumes” were grouped with vegetables and were in the “food groups to encourage” category. In the recently released MyPyramid healthy eating icon, beans share the second-narrowest slice with meat and nuts. Critics say, on the surface, beans, fish and nuts don’t get a fair shake in this omnibus category, but the detailed information of MyPyramid suggests, “Choose dry beans or peas as a main dish or part of a meal often.”

Beans are full of fiber because they usually are consumed after they are thoroughly mature, allowing most of the carbohydrates to transform to fiber. Green baby beans or peas don't have as much fiber, and their carbs are usually sugar. The amount of fiber varies with variety and growing conditions. Beans that are eaten in their pod are even richer in fiber.

While fiber is helpful simply in reducing caloric intake, it also appears to have other roles in maintaining good health. The particular mix of fiber, complex carbs and nutrients in beans is credited with having a role in controlling cancer, improving cardiovascular health, maintaining healthy levels of insulin and other positives.

There was, of course, one major drawback for all beans: the inability of the human digestive system to break down the small sugars (stachyose, raffinose and some other small polymers) in the upper digestive system, leading to bloating and flatulence in the lower gastrointestinal tract.

While the result of eating lots of beans in any form was hilarious in the 1970s movie “Blazing Saddles,” only Mel Brooks would think the actual symptoms funny. Processed beans have changed since then. Research has found several ways of eliminating the effect of those small sugars, making soy and its brother beans useful for a lot of reasons.

USDA’s list of “dry beans and peas” includes this dizzying array: adzuki beans, baked beans, black beans (turtle beans), black-eyed peas, chickpeas (garbanzo beans), cranberry beans, dark- and light-red kidney beans (Mexican beans), Great Northern beans (white beans), green and red lentils, soybeans (edamame), kidney beans, lentils, lima beans, navy beans (pea beans), pink beans, pinto beans, small red beans (Mexican red beans), split peas, tofu (soybean curd) and yellow-eyed beans.

Solution for gluten intolerance

In addition to beans’ use as a plated food item, there is increasing interest in their use as an ingredient. In particular, bean flours of various types are now appearing in the marketplace. Bean flour provides protein, some carbs and a lot of fiber, as well as additional nutrients – and they can be substituted in many applications that use wheat and other traditional flours. An added benefit is bean flours can be eaten by people with celiac disease, whereas wheat products (as well as rye, barley, and to a lesser extent, oats) cause trouble.

Also known as gluten intolerance, celiac disease is a genetic disorder that affects one in 133 Americans, especially people of northern European descent. Those affected suffer damage to the villi in the intestines when they eat certain food-grain antigens (toxic amino acid sequences) that are found in wheat, rye and barley, according to the Celiac Foundation. That cuts out a lot of the traditional flours. There is a cascade of symptoms, including early onset osteoporosis, constipation, bloating, fatigue, irritable bowel syndrome and vitamin deficiencies.

There isn’t a cure, per se, according to celiac disease expert Dr. Joseph Murray of the Mayo Clinic in Rochester, Minn. “Lifelong adherence to a gluten-free diet is necessary to maintain health. The gluten-free diet is restrictive, but it doesn’t have to be uninteresting.” With the current interest in whole grains, the development of ingredients from beans of all types, lentils, garbanzo beans, and similar legumes, means greater variety for the celiac disease sufferer. Many companies working with beans as an ingredient note their low glycemic index, useful for diabetics.

Bean production has been on a slight decline for years, and was just more than 21 million lbs. in 2004, according to USDA. However, the bean crop in Canada appears to have increased. In the U.S., they are mostly grown in California and the northern tier of states. For farmers in the Grain Belt, beans provide a useful alternative crop to corn and other high nitrogen-using plants. By alternating corn with beans, the application of nitrogen, which is expensive and has environmental implications, can be reduced.

Because of the volatility in soybean prices, “edible” beans, as they are called by farmers, are a welcome addition to salable crops. Kidney beans, small red beans, pinto beans and navy beans often are sold to canning companies. Bush Brothers & Co., Knoxville, Tenn., has built a small empire on beans. In addition to its famed baked beans and chili beans, Bush’s canned products include black beans (the key ingredient in many Cuban, Mexican and Puerto Rican dishes), blackeye peas (a staple in the South) and cannellini beans (brings a meaty flavor to traditional Italian dishes).

Bush Brothers also has done much research to improve acceptability of baked beans. Company patents for reducing discomfort describe methods of heating for specific times and cooling to specific levels.

While there is a lot known about bean production in the U.S. and Canada, much less is understood about consumption patterns. Beans were widely consumed in the early parts of the 20th century, peaking during World War II at about 11 lbs. per person. Then they began to decline, but started to rebound between 1997-1999 years, recovering to about 7.7 lbs. per person.

Pinto beans, navy beans and kidney beans were the most popular beans during the last USDA consumption survey. According to USDA data, on any given day about 14 percent of Americans eat at least one dish containing cooked dry beans.

The assumption that an increase in Hispanic population drove an increase in bean consumption may be accurate. Even though not a specific type of bean, refried beans, which may be made from several different beans, are next in line of popularity.

Some specialty beans, such as black beans, which have become a favorite in the past few years, are generally eaten at standard (not fast-food) restaurants – however, they still account for just a half-pound per capita annually. Some 39 percent of cooked dry beans are consumed in the southern states, and an additional 38 percent consumed in the western states. Only 11 percent of the cooked dry beans were eaten in the northeastern states – so much for Boston being nicknamed "Beantown."

Various bean pastes have been used by a few companies as a fat replacer as the soluble fiber has great water-holding properties, according to one formulator.

Beans make healthy flour

While beans as a semi-vegetable are enjoying some new respect, their use as a hidden ingredient, particularly in flours, also seems to have great potential.

Bob’s Red Mill (www.bobsredmill.com) is a 25-year-old Milwaukie, Ore., company that has reached national distribution with a broad line of bean flours, as well as supplying commercial quantities of these ingredients. Bob’s bean flours aren’t organic, but the “stone-grinding” method promoted on packaging has a natural feel that consumers find attractive.

Bob’s credits some of its success to concern over celiac disease. “The size of the gluten-free market caught us somewhat by surprise,” says Matthew Cox, marketing coordinator for Bob’s Red Mill. “We identified whole grains as a business we wanted to be in, and we produce and sell white, navy, garbanzo, black, and fava bean flour. The bean flours add body and flavor as well as protein and fiber to rice flour mixes, and we use them in our own gluten-free baking mixes.” These baking mixes include brownie mix, all-purpose baking mixes, pancake mixes and bread mixes.

Cox also acknowledged a boost from people with allergens other than celiac disease, as well as those interested in low-glycemic index foods.

Ontario is a major source of certain beans, and the province has developed a considerable amount of nutritional information. The Ontario White Bean Producers claim that white pea beans (navy) are the richest source of vegetable protein, claiming 17 g of protein per cup of cooked beans, a gram of lipid with no cholesterol, and 13 g of dietary fiber. They are also a rich source of folate, iron, calcium, phosphorus, magnesium and zinc. A number of Canadian companies report that they are working with bean flours, and some have been supplying U.S. companies as well.

Heartland Ingredients LLC (www.heartlandingredients.com), Ubly, Mich., has produced a line of bean flours partly based on research by Michigan State University. The research sponsored by GREEEN (Generating Research and Extension to meet Environmental and Economic Needs) developed a method to reduce those small oligosaccharides that fail to be metabolized in the upper intestine, leading to digestive disturbances.

Kirk Dolan of Michigan State worked on this phase of development, which included work with enzymes (similar those used in products like Beano, the enzyme treatment for those who suffer abdominal distress when they eat beans or related foods). The enzymes break down the small oligosaccharides into metabolizable sugars. Dolan also developed techniques of soaking and germinating the beans to remove the small sugars (and therefore reducing carbohydrates) altogether.

“A selected combination of soaking, germinating, and enzyme treatment allows oligosaccharides (such as stachyose and raffinose) to be reduced by 35 to 60 percent, depending on the concentration of oligosaccharide that was present in the bean originally,” says Dolan. 

Heartland Ingredients is a joint venture of the Michigan Edible Bean Co-op and the Minnesota farmer alliance FarmConnect. The business was built as an outlet for bean-based products and is designed to meet the needs of those who require a gluten-free diet. The organization is just over a year old, and its first products are now beginning to reach the marketplace. Heartland offers six types of gluten-free pasta, navy bean flour and pinto bean flour. 

Jim LeCureux, general manager of Heartland, claims the market segment is growing at a rate of about 18-20 percent per year – growing in part by the improving ability to diagnose celiac disease. The emphasis on whole grains and low glycemic index has helped expand the category as well.

“The pasta products are well accepted,” he says. “Most celiac patients welcome them, and say they taste what they remember pasta tasting like before they embarked on a gluten-free diet.”

Along with the development of ingredients aimed at special users has been the wider interest in organic foods. Beans are a natural for this segment.

Purcell Mountain Farms (www.purcellmountainfarms.com), Moyie Springs, Idaho, is an organic producer using the Unifine Milling Process, which reduces beans to a fine powder in air and prevents heat build-up. Purcell’s garbanzo bean flour (also called chana dal or gram flour) retains the natural oils, producing 10 calories of fat per ¼ cup serving (32 g). 

Purcell Mountain will grind any beans to order. “We’ll make any kind of bean flour that is required,” says Sabina Dahlman, co-owner of the business. “We use the cool process mill to avoid getting the flour hot, so the oils stay in place and taste good.” About the garbanzo bean flour, she adds, “Chefs particularly like the product. It tastes good, and is easy to use.”