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ARS Home » Midwest Area » Peoria, Illinois » National Center for Agricultural Utilization Research » Functional Foods Research » Research » Publications at this Location » Publication #367554
Research Project: Innovative Processing Technologies for Creating Functional Food Ingredients with Health Benefits from Food Grains, their Processing Products, and By-products

Location: Functional Foods Research

Title: Extraction of proteins and pasting and antioxidant properties of soybean hulls

Author
item Liu, Sean
item Chen, Diejun
item Singh, Mukti
item Xu, Jingyuan - James

Submitted to: Journal of Food Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/4/2019
Publication Date: 10/17/2019
Citation: Liu, S.X., Chen, D., Singh, M., Xu, J. 2019. Extraction of proteins and pasting and antioxidant properties of soybean hulls. Journal of Food Research. 8(6):66-77. https://doi.org/10.5539/jfr.v8n6p66.
DOI: https://doi.org/10.5539/jfr.v8n6p66

Interpretive Summary: Soybean hulls are a by-product from soybean processing and have long been used as animal feed. It would be economically advantageous to use soyhulls in foods, either as direct ingredients or feedstock for extracting valuable products such as food proteins. This study examined the possibility of ground soy hulls as potential high-dietary fiber food ingredients by investigating important physicochemical properties of ground soyhulls such as water holding capacity, pasting properties, and antioxidant activities of soybean hulls. In addition, the conditions for extracting proteins from soybean hulls including optimum pH, as well as homogenizing and separation methods for extraction, were also studied. Higher protein content in extracts and recoveries was obtained with extraction at pH 9 with a washing step. Ground soyhulls and the extracted proteins from ground hull powders and other extracts such as dried supernatant (14% protein) and sediments (7-8% proteins) should be good protein and fiber rich food ingredients for several food categories. This research explored the great potential of converting the low value by-products of soy processing into value-added functional food uses while reducing food and agricultural wastes.

Technical Abstract: Soybean hulls are a by-product from soybean processing for oil and soy meal production which comprise approximately 8% of the whole seed. This study investigated water holding capacity, pasting properties, and antioxidant activities of soybean hulls. In addition, the conditions for extracting proteins from soybean hulls including optimum pH, as well as homogenizing and separation methods for extraction, were also studied. Higher protein content in extracts and recoveries was obtained with extraction at pH 9. Using sieve separation may be an effective way to extract proteins from hulls for industrial applications. The precipitated protein content increased from 51.52% to 59.29% after purification by washing with water once; however, after two washes, no further improvement was shown. The extracted proteins and the ground hull powders (10% protein), dried supernatant (14% protein) and sediments (7-8% proteins) along with valuable fibers should be good food ingredients for several food categories. This research explored the great potential of converting the low value by-products into value-added functional food uses along with the benefit of reducing food wastes.