title: Integrating alkaline extraction of proteins with enzymatic hydrolysis of cellulose from wet distiller's grains and solubles.
abstract: Fractionation of distiller's grains into value added products may serve to improve the economic viability of dry grind corn ethanol facilities in the wake of variable corn and ethanol prices. This research is aimed at creating a high protein, high lysine product from the grain using alkaline protein extractions in conjunction with hydrolysis of the remaining fiber to sugars which are then fermented to ethanol. Alkaline extractions improved the lysine content in protein products, although protein solubility did not exceed 45% of the total protein. In addition, oligomeric carbohydrates, starch, and other water solubles were also extracted, leading to a low purity protein product. Resulting sugar yields following ammonia fiber expansion (AFEX) pretreatment were also lower for extracted distiller's grains. From these experiments, it does not appear likely that alkaline extraction is a useful tool for fractionation of distiller's grains. However, pretreatment and hydrolysis can be an effective tool for further fractionation of protein.
authors.affiliation: Biomass Conversion Research Laboratory, Department of Chemical Engineering and Material Science, Michigan State University, 3900 Collins Rd., Lansing, MI 48910-8596, United States. balsbrya@msu.edu
authors.forename: Bryan
authors.initials: B
authors.lastname: Bals
authors.forename: Venkatesh
authors.initials: V
authors.lastname: Balan
authors.forename: Bruce
authors.initials: B
authors.lastname: Dale
mesh_terms: D000641:Ammonia / Q000737:chemistry; D001674:Bioelectric Energy Sources; D002241:Carbohydrates / Q000737:chemistry; D002482:Cellulose / Q000737:chemistry*; D002523:Edible Grain / Q000378:metabolism; D000431:Ethanol / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007220:Industrial Waste; D008239:Lysine / Q000737:chemistry; D011506:Proteins / Q000737:chemistry; D012995:Solubility; D013213:Starch / Q000737:chemistry; D014867:Water / Q000737:chemistry; D003313:Zea mays / Q000737:chemistry
chemical_list: D002241:Carbohydrates; D007220:Industrial Waste; D011506:Proteins; D014867:Water; D000431:Ethanol; D000641:Ammonia; D002482:Cellulose; D013213:Starch; D008239:Lysine