Development of white finger millet probiotic beverage using Lactocaseibacillus rhamnosus (LGG): Process optimization and study of physicochemical and nutritional properties

Abstract

AbstractWhite finger millet (WFM) is a repository of vital nutrients and minerals. This study aims to develop the white finger probiotic beverage, optimize the ingredients level for the formulation, and study the physiochemical and nutritional properties of the formulated vegan WFM probiotic beverage (WFMPB). The optimum condition for the development of WFMPB was obtained by Box–Behnken design. The independent variable like WFM flour (10–14% w/v), microbial inoculum (1–5% v/v), and sugar (5–15% w/v), and their impact on the response variables like total solid content (TSS), pH, microbial count, and viscosity were studied for optimization. Increment in the amounts of WFM flour and inoculum levels had a significant impact on the microbial load and pH. However, sugar levels affected viscosity and TSS. The combination of 14% WFM, 1% microbial inoculum, and 5% sugar showed maximum desirability of 0.975, with the highest sensory score (8.34), TSS of 15.4 °Brix, pH of 4.33, the microbial load of 9.45 log (cfu/ml) and viscosity of 43.32 cP. WFMPB consists of 11.91% carbohydrates, 1.46% protein, 0.89% fat, and 0.632% crude fiber. The rheological studies showed that WFMPB is a shear‐thinning fluid (n ˂ 0.1). The study revealed that WFM is the better carrier matrix for the LGG growth and can be an alternative for the strict vegan and lactose‐intolerant consumers.