Sugary kefir grains as the inoculum for developing a low sodium isotonic beverage

The objective of this study was to apply for the first time sugary kefir to produce a new isotonic with low sodium. Additionally, the microbial community profile of grains and fermented kefir was evaluated through metataxonomics. The kefir grains were inoculated into filtered water containing 40 g L^-1 sugar at 25 °C for 48 h. Grains and beverage samples were collected at 0, 24, and 48 h for DNA extraction. The grains were separated, and the beverage was used to prepare the isotonic. The isotonic consisted of kefir (85% v/v), pasteurized juice (15% v/v), sodium citrate (0.2 g L^-1), sodium chloride (0.427 g L^-1), maltodextrin (22 g L^-1) and citric acid (0.7 g L^-1). The physicochemical and microbiological parameters were performed on days 0, 7, 15, and 30. All isotonic obtained presented sodium content below the commercial control. The presence of lactic acid bacteria and yeasts in all periods evaluated demonstrated the viability of isotonic kefir. Through metataxonomy, the genus Ethanoligenens was described as dominant for the first time in sugary kefir. Furthermore, the microbial diversity in the beverage was higher than that observed in the grains. This study provided a new low sodium isotonic based on sugary kefir for the first time.