Cereal Chem 66:506-509   |  VIEW ARTICLE

Protein-Rich Residue from Ethanolic Fermentation of High-Lysine Dent, Waxy, and White Corn Varieties.

Y. V. Wu. Copyright 1989 by the American Association of Cereal Chemists, Inc. 

Corn is the predominant biomass used to make alcohol by fermentation in the United States. Dent corn has been used exclusively for fermentation so far; no information is available for other types of corn. Ground high-lysine (containing the opaque-2 gene), dent, waxy, and white corns were fermented to make alcohol. The stillage residue was then fractionated into distillers' grains, centrifuged solids, and stillage solubles. The highest yield of alcohol and lowest yield of fermentation residue were obtained from dent corn. The centrifuged solids had the highest protein content (37-49%), followed by distillers' grains (31-35% protein). Amino acid analyses of the stillage fractions from high-lysine corns contained higher lysine contents than corresponding fractions from other types of corns. Corn distillers' grains with solubles had a higher ash content than the corn varieties themselves; however, mineral composition of corn types or among corn distillers' grains with solubles was not significantly different. Distillers' grains from high-lysine corn have potential for use in human food and nonruminant feed because of higher predicted protein quality than those from dent corn.