On the Change of Ralative Content of Tasty and Non-tasty Amino Acids during Pickling Process of Sunki-pickles

Studies on the Japanese Pickles Sunki Part XIV

Abstract

Following results were obtained from chemical analyses and sensory tests of Sunki pickles prepared from Gishigishi (Rumex japonicus) and "Bulgarian Yoghurt" (Meiji Dairy Co.) as the source of Lactobacillus bulgaricus and Streptococcus thermophilus:
(1) Favourable pickling period for 500g of Gishigishi-leaves with 50g of the yoghurt at 5°C was 4 weeks. (2) A decrease of alanine, and an increase of aspartic acid which is a tasty amino acid, were observed during pickling process, and oxaloacetic acid was detected in the pickling juice. (3) Above mentioned results suggest formation of aspartic acid by transamination of alanine to oxaloacetic acid, which might be derived from malic and succinic acids in the leaves.