Development and optimization of apricot-based water kefir fermented beverage: A comprehensive microbial, physiochemical, and proximate evaluation

Water-kefir is a known probiotic-rich fermented drink developed by the fermentation of sucrose using water kefir-grains. These grains contain beneficial lactic acid bacteria (LAB), acetic acid bacteria (AAB), and yeast. It helps in the improvement of gut health, digestion and immunity because of its high probiotic content. Apricot fruits contain vitamins like A, C, and E; fiber; as well as antioxidants that promote digestion, heart function and skin health. Apricot-based water kefir drink (AWKD) is a functional as well as novel drink that provides probiotics and vital nutrients, hence preserving the gut flora and health. The combination of both offers a healthier, more refreshing, and natural alternative to the standard probiotic drinks. The aim of this study was to optimize AWKD through response surface methodology (RSM) with a Box-Behnken design. Dried apricot juice (16.6-23.3% w/v) along with brown sugar (4-6% w/v) was fermented with water kefir grains (4.6-10% w/v) at 32°C for 24 hours. The impact of all three variables on pH, total bacterial load (CFU/mL), and overall acceptability (7-point hedonic scale) were examined to identify the optimal concentration of the product. The physicochemical, proximate, antioxidant and shelf-life analyses of the optimized AWKD were evaluated using AOAC international methods. The optimized concentration was found to be 8% (w/v) water-kefir grain, 8% (w/v) brown sugar and 20% (w/v) dried apricot, having a pH of 3.86, a total bacterial count 2.73 × 10⁸ CFU/mL and the overall acceptability value of 6.89. This result suggested its profound potential as a functional probiotic beverage. This novel and innovative probiotics beverage may be a suitable substitute to vegan and lactose intolerant individuals.