Restoration of kefir grains subjected to different treatments

Abstract

The aim of the study was to find a way to recover the quality of kefir grains that had been subjected to the following treatments: homogenisation, rinsing the grains with water, freeze-drying and milling, freezing in liquid nitrogen and then frozen storage, and cool storage. The grains were studied in respect of their later replication in milk, their size and their microbiota composition. The daily transfer of treated kefir grains, except freeze-dried ones, into fresh milk was effective in respect of the recovery of their growth dynamics, size and microbiota balance. The growth dynamics of grains in milk seems to be a very good indicator of their vital and technological functions. © 2011 Society of Dairy Technology.