Stimulation of Kefir Grains by Different Juices to Produce Novel Kefirs

Kefir grains are symbiotic microbiota starters in the production of dairy products such as fermented milk, kefir. In recent decades, microbial symbiosis in kefir grains and its role in fermentation have attracted a lot of attention. This study aimed to obtain novel kefirs with different characteristics by “stimulating” kefir grains with juices of Actinidia chinensis, Solanumly copersicum, Daucus carrot, and Lactuca sativa, respectively, before being used as starter cultures for kefir fermentation. Then, compositions of the predominant microbiota in novel kefirs were determined. These novel kefirs showed changes in their physiochemical characteristics and enhanced antimicrobial activities against Shigella dysenteriae, Candida albicans, Staphylococcus aureus, Serratia marcescens, and Escherichia coli. Therefore, preprocessing of kefir grains with natural substrates could be a feasible strategy in the production of novel kefirs with different flavors and various health benefits.