SINKI - A TRADITIONAL LACTIC-ACID FERMENTED RADISH TAP ROOT PRODUCT

Sinki, a non-salted fermented radish tap root product, is traditionall y consumed as a base for soup and as a pickle in some north-eastern st ates of India, in Nepal and a few places of Bhutan. A total of 453 str ains of lactic acid bacteria were isolated from 40 samples of sinki. T hey belonged to either Lactobacillus plantarum or Lactobacillus brevis . In the substrate, in addition to these two, Lactobacillus fermentum was present. Sinki was dominated by L. plantarum followed by L. brevis , with their prevalence in 100% of the samples. In order to study the changes in proximate and microbial composition accompanying fermentati on, the process conditions for the production of sinki were optimized. Glass jar as a fermentation container and 12 days' fermentation at 30 degrees C were found optimum. During fermentation under optimized con ditions, the pH of the fermenting mass dropped from 6.7 to 3.3. This w as due to an increase in titratable acidity from 0.04 to 1.28%. The fe rmentation was initiated by heterofermentative L. fermentum, followed by another heterofermentative L. brevis, and finally succeeded by homo fermentative L. plantarum.