A comprehensive review of the production, beneficial properties, and applications of kefiran, the kefir grain exopolysaccharide

The natural starter for kefir production is kefir grains, which house many yeast and bacterial species in a polysaccharide matrix, called kefiran. Kefiran has many beneficial properties, including therapeutic and rheological, that make it a valuable biopolymer with widespread industrial applications, including food packaging, food stabilizing, tissue engineering, and drug or probiotic delivery. The biological performance of kefiran has yet to be completely recognized and exploited. Various production challenges, including cost inefficiency and inhibition by acid production during fermentation, have prevented large-scale, commercial production kefiran. Here, we review the production, biological properties, and applications of the kefiran exopolysaccharide, focusing mainly on its application for the food industry. We identify the knowledge gaps in the literature, indicating a need for further exploration on the applications of kefiran. Future research, coupled with the innovations described here, should prioritize kefiran as a biopolymer and food additive, pointing its applications in a new direction.