Nutritional, microbial dynamics, safety modelling and sensory characterization of a beverage obtained from fermented pearl millet-milk mixture

This study describes the nutritional, microbial population dynamics, stability, and sensory characteristics of a functional pearl millet-milk fermented beverage (PMFB) made using Limosilactobacillus fermentum (MS005). Fermentation was carried out for 16 h, and the obtained Raabadi-like beverage contained 8.75 log10 CFU/mL of lactic acid bacteria (LAB). The proximate composition of the beverage was as follows: carbohydrates (6.19%), protein (3.65%), fat (0.96%), ash (1.39%), and moisture (87.81%). The physicochemical properties were determined as pH 5.06, total soluble solids of 8.33 °Brix, total titratable acidity of 0.52%, dry extract content of 12.19 g/100 mL, and viscosity of 63.00 cP. Furthermore, mineral profiling of the fermented beverage demonstrated the presence of essential micronutrients, mainly iron (7.29 mg/L), zinc (6.44 mg/L), calcium (1023.08 mg/L), and phosphorus (243.60 mg/L). The microbial dynamics and shelf life of the beverages were evaluated using a food spoilage and safety predictor model. The microbial dynamics data for LAB and shelf-life analysis using Food Spoilage and Safety Predictor models (FSSP) demonstrated that the predicted LAB growth at 4 °C aligned with the test findings. Based on the findings, it was concluded that the PMFB was safe to consume for one week when stored at refrigerator temperature (4 °C), but only for one day when stored at room temperature (25 °C). The overall acceptance score for the beverage’s sensory analysis was 6.6 (like moderately), which is an average (sensory data) across 35 panellists who consumed the product. The developed prototype is new, organoleptically appropriate, safe, and stable for at least one week when stored in the refrigerator.