Development of a Prototype of a Fermented Peanut Beverage Using Plant-Derived Lactobacilli

The growing demand for plant-based functional foods has encouraged the development of non-dairy fermented beverages able to deliver viable microorganisms and improve the technological and nutritional value of plant matrices. This study aimed to develop a prototype fermented peanut beverage using Lactiplantibacillus plantarum strains and to evaluate their technological performance, stability, and functional potential. Two plant derived strains, L. plantarum F1B and LpAv, and the commercial probiotic L. plantarum 299v were assessed in animal-free culture media and used to ferment peanut extract supplemented with sucrose and yeast extract. Fermented beverages were characterized through microbiological, physicochemical, rheological, peptide profile, refrigerated storage, and simulated gastrointestinal digestion. The selected formulation allowed all strains to reach pH ≤ 4.5 after 6.5 h, with LAB counts of 8.6–9.0 log CFU/mL. Lactic acid was the main fermentation product, and oxalic acid levels were significantly reduced. Fermentation increased peptide signals and improved rheological behavior, generating pseudoplastic beverages with higher viscosity than the control. LAB counts remained ≥8 log CFU/mL after 28 days at 4 °C, although gastrointestinal resistance after storage was strain-dependent. Taken together, L. plantarum strains showed promising technological and functional properties for developing fermented peanut-based beverages. The nutritional properties of peanut, together with the fact that it supports the growth and survival of LAB in a fermented beverage, positions peanuts as a candidate which deserves further studies in the space of fermented functional foods.