Stability of Glutamic Acid and Monosodium Glutamate Under Model System Conditions: Influence of Physical and Technological Factors

Abstract

ABSTRACT The stability of glutamic acid and monosodium glutamate as regards pH, temperature and oxygen was studied during storage and two thermal processings, the residual products and those which appeared being determined. The initial molecules only change into pyrrolidonecarboxylic acid, never into glutamine nor γ‐aminobutyric acid. Preservation is good in all cases at pH 0 and pH 14, but glutamic acid is converted to pyrrolidonecarboxylic acid at intermediate pH values. The change is favored by pH values ranging from 2 ‐ 3, by temperature increase and by oxygen.