The General Composition, Inorganic Cations, Free Amino Acids and Organic Acids of Special Vinegars

Studies on the Special Vinegars Part I

Abstract

The general composition, inorganic cations, free amino acids and organic acids were examined on 11 kinds of special vinegars in Japan, which are commercially available at relatively high prices. The data obtained were compared to those of ordinary rice vinegars. The results were as follows: (1) Not much difference in general composition was detected among these vinegars, though sediments were found in most samples of black vinegars which emphasized addition of caramel during its preparation. (2) The major inorganic cations present in special vinegars were found to be Na followed by K and Mg. (3) The total free amino acid contents of special vinegars ranged from 56.9 to 362.6mg/100ml were rich in alanine, leucine, lysine, valine and glycine. The special vinegars were high in amino acid components as compared to the ordinary rice vinegars. The difference in their amount seemed to be caused by the difference in the raw materials and method of preparation. The ratio of essential amino acids to the total free amino acids ranged from 45 to 50%. (4) Lactic acid was the most abundant followed by pyroglutamic acid among organic acids except acetic acid in special vinegars. The results of this study showed that special vinegars which are sold at relatively high prices were doubtful in terms of quality and prices.