Influence of pH on Available Amino Acid Concentrations in Fermented Cornheal

Cornmeal was fermented at 45°C for 1, 2, 3, and 4 days. Meal was also allowed to ferment without a pH adjustment at 45°C for 1, 2, 3, and 4 days. The fermentation without a pH adjustment produced the largest concentrations of lysine, methionine, and tryptophan. Of the pH ranges tested, lysine was best produced at pH 5.0-5.5, methionine at 4.0-4.5, and tryptophan at 4.0-4.5. All samples fermented at pH 4.M.5 or at pH 5.0-5.5 for 1 and 2 days were significantly (P<0.05) higher in lysine, methionine, and tryptophan than nonfermented corn. Fermentations of 1 and 2 days produced the highest concentrations of available amino acids, which then decreased by days 3 and 4. Authors Nanson and Fields are with the Dept. of Food Science & Nutrition, College of Agriculture, Univ. of Missouri-Columbia, Columbia, MO 652 11.