Effect of storage parameters on freeze-dried kefir grains

Abstract

The purpose of this study was to use freeze-drying to preserve microbial activity while extending the shelf life of kefir grains and to determine the best storage temperature. Freeze-dried kefir grains were lyophilised and were later stored in a multilayer plastic film with a moisture barrier for 90 days at varying temperatures. Microbial activity continued until the 60th day of storage at 4 °C. PCR analysis was performed to determine Lactobacillus kefiranofaciens as an indicator kefir micro-organism. It was concluded that the conservation of kefir grains by freeze-drying protects the natural embedded microbiota; therefore, both the shelf life of kefir grains and the consumption of natural kefir increase.