Research explores soy’s place in pet food nutrition

Soybean meal continues to be key in our everyday lives through pet food

Even the most beloved animals in our lives can thrive by consuming soy. Two research projects funded by the Kansas Soybean Commission are focused on enhancing the nutritional profile of soy in pet foods and changing the grain-free narrative.

Ownership of companion animals is on the rise, with over half of U.S. households owning a pet and 40 percent of U.S. households owning a dog. The sentiment toward these companions is shifting, as well, according to Petfood Industry Magazine. Many pet owners are mirroring their pet’s cuisine to their own dietary preferences – this means plant-based takes up a substantial share of manufactured pet foods. At the same time, consumers can find an array of options on store shelves touting “grain-free” formulas.

A project at the University of Kansas led by Dr. Ana Rita C. Morais in the Department of Chemical and Petroleum Engineering is working toward an end goal of producing a soybean-based single-cell protein that meets desired nutritional specifications in the pet food industry. Current use of defatted soybean meal in pet food formulations is considered to have challenges including palatability and flatulence issues, presence of nondigestible oligosaccharides and requirement of lysine enrichment to meet a desired amino acid profile, Morais says. Single-cell protein, which is extracted from cultured yeasts, more closely resembles the essential amino acids found in meat protein, and could help balance the amino acid profile in soybean meal on a nutritional level.

The KU project encompasses a one-year timeline divided into three phases before being put to the test in a feeding study through Hills Pet Nutrition. Phase one of chemically characterizing defatted soybean meal feedstock covered July and August. Phase two, still ongoing, involves enzymatic hydrolysis of oligosaccharides in defatted soybean meal into monosaccharides.

“We did characterize our [defatted soybean meal] in terms of chemical composition: cellulose, hemicellulose, lignin, starch, protein, ash and moisture,” Morais reports. “Based on the carbohydrate content, mainly starch, glucan, galactan and arabinan; an enzymatic cocktail composed of amylases and galactonases, have been developed to convert these carbohydrates into monomeric sugars.”

She says her team has obtained liquors rich in glucose and galactose through the process which will be further used to produce single-cell protein. Next up in the project is developing the single-cell protein.

“Our success in achieving the described goals of the project will enable the pet food industry to have access to soybean-based, antigen-free, highly digestible protein concentrates, with a more balanced amino acid profile,” Morais says.

Up the river at Kansas State University, Dr. Greg Aldrich in the Department of Grain Science and Industry is using fermentation technology to increase soybean’s nutritional value in pet foods, while increasing consumer acceptance of soy as a valuable ingredient in their furry companions’ diets. Aldrich, too, acknowledges the “anti-nutritional” factors in soybean meal, including the oligosaccharides and generally low digestibility.

Processes to address these challenges include heat treatment, genome modification and addition of enzymes, though microbial fermentation of soybean meal may be the best option to reduce the negative factors, Aldrich says. The project’s objective is to use fermentation to resolve flatulence issues associated with oligosaccharides, eliminate trypsin inhibitors and increase bioactive molecules like isoflavones. The enhanced soybean meal product would then be studied as an ingredient in pet foods.

Soybean farmers win with diversified soybean uses that contribute to soy’s competitiveness in the marketplace. Exploring the incorporation of soy in pet nutrition adds one more checkmark to the growing list of reasons why soybeans are the most important bean in the world’s economy.