Effects of temperature and salt concentration on microbial populations of "NISHINZUKE" fermentation

Abstract

The effects of temperature and salt concentrations for fermentation of "NISHINZUKE" were investigated and the following results were obtained. Though gram-negative bacteria were predominant among the microorganisms on the early stage, they were killed and decreased by accumulation of lactic acid produced by lactic acid bacteria during storage. The bacteria counts of Lactococci were about 106/g in the first stage, but those of Lactobacilli were about 103/g. The bacteria counts of both Lactobacilli and Lactococci increased to about 5 × 108/g at 10°C for 5 day. In the "NISHINZUKE" fermented at 10°C, marked increase in Pichia spp. were found in the later stages of fermentation. The quality of "NISHINZUKE" was stable under at 5°C for 35 days but unstable at 10°C.