Recovery and use of value-added corn functional ingredients

South Dakota State University/Padmanaban Krishnan

The economic value of traditional cash crops are enhanced by finding new uses in diversified products. Such applications are particularly effective in enhancing health, nutrition and disease prevention. Considerable potential exists for the recovery of useful moieties from the waste streams and co products of corn processing. Major constituents recovered as feed and food ingredients from corn are protein and dietary fiber, both of which are beneficial for animals and humans. The latter was the focus of a previous study by PI Krishnan. Beyond protein and fiber, other useful compounds such as pigments, yeast metabolites, precursors of vitamins, and DDG oils may have economical value and need to be optimized. Zein, a corn protein, has many industrial applications. Corn remains the principle substrate for use in industrial ethanol production. As the ethanol industry continues to grow, so have the large quantities of residues generated from the industry. Current projections estimate 44.7 million tons of DDG. Minnesota’s 21 ethanol plants produce approximately 3 million metric tons of DDG annually. As feed markets become saturated, new avenues and markets need to be explored. The price per unit of protein for corn DDG is $4.64 in contrast to $6.61 for soybean meal. Development of Functional Foods, products with disease prevention properties, is one such promising application. The market size for functional foods is about $7.5 billion in the US and $24 billion globally (Daniels, 2011). These markets continue to expand. However, research and development efforts are needed for producing functional food ingredients and novel processes for bioactive plant compounds. A systematic approach and platform will be pursued for products and processes that will be economically feasible to implement. This investigation will be done in close collaboration with ethanol processors and food ingredient companies. As starch and fermentable carbohydrates are the only constituents removed from corn in the ethanol plant, residues from ethanol plants can serve as starting materials for new products.