Cereal Chem 42:539 - 545.  |  VIEW ARTICLE

Fungus Deterioration of Rice: Effects of Fungus Infection on Free Amino Acids and Reducing Sugars in White and Parboiled Rice.

H. W. Schroeder. Copyright 1965 by the American Association of Cereal Chemists, Inc. 

Growth of Fusarium chlamydosporium in Bluebonnet 50 and Belle Patna rice greatly increased the numbers and concentrations of free amino acids as determined by paper chromatography. Those detected in noninfected rice were aspartic acid, glutamic acid, serine, glycine, threonine, alanine, valine, leucine(s), tyrosine, asparagine, proline, methionine, gamma-amino-n-butyric acid, and glutamine. In infected rice, histidine, lysine, arginine, phenylalanine, tryptophan, cysteine, and cystine were also detected. A marked decrease in concentration of glutamic acid, histidine, asparagine, proline, and glutamine, with corresponding increases in valine, leucine(s), phenylalanine, tryptophan, and methionine, resulted from parboiling infected rice. The bulk of the reducing sugars detected was glucose. Glucose was not found in the infected rice but reappeared when infected rice was parboiled. Studies with rice infected and discolored by F. chlamydosporium indicated that the change in color associated with parboiling was not solely a result of the browning phenomenon (Maillard reaction).