Elaboración de kéfir de uvilla (Physalis peruviana) con diferentes niveles de oca (Oxalis tuberosa)

Abstract

This research aimed to prepare kefir from cape gooseberry (Physalis peruviana) with several levels of oca (Oxalis tuberosa). In this process, a Submerged fermentation was essential using a mixture containing 6% panela, 6% cape gooseberry pulp, 15% Tibetan microorganisms, and 73% distilled water. Time and temperature measurements took 72 hours. After reaching the fermentation time, the biomass of Tibetan microorganisms was removed. The next step in this procedure involved an analysis of the beverages derived from cooked oca pulp at different levels (10%, 20%, and 30%), focusing on physicochemical properties, including reducing sugars (%), Brix degrees (°Bx), lactic acid content (%), density (g/cm³), ethyl alcohol content (%), protein content (%), ash content (g), and pH. Concerning Microbiological analyses, they included inoculation with the streak plate method with several dilutions based on the microorganism under research. In terms of organoleptic evaluation, a hedonic scaling test was administered to 30 untrained panelists, while an economic analysis using the Benefit/Cost indicator was also necessary. Statistical analyses were carried out using the "Info Stat" statistical software, applying a Principal Component Analysis (DCA) and the Tukey mean separation test (P<0.05). The sensory evaluation included the Kruskal-Walli’s test. The results revealed that the treatment containing 30% oca pulp exhibited higher physicochemical parameters, with all levels showing an absence of molds, Escherichia coli, and total coliforms. In contrast, lactic acid bacteria and yeast counts were 1.1310^7 and 6.5010^4 CFU/ml, respectively. Additionally, this treatment yielded a more favorable benefit-to-cost ratio of $2.38.