Caracterización preliminar de dos fermentos de kéfir de agua después de cinco días

Water kefir is a fermentation system composed of bacterial and yeast communities whose composition depends on the inoculum and fermentation conditions. This study preliminarily characterized the physicochemical, culture-based microbiological, microscopic, and phenotypic properties of two independent fermentations prepared from the same batch of water kefir grains. Each unit contained 40 g of grains, 30 g of commercial yellow panela, and 1 L of bottled water and was evaluated after five days. In M1 and M2, pH and soluble solids were determined from three technical readings per sample; growth on a laboratory-formulated nutrient medium, morphology by Gram staining, catalase activity, and an exploratory metabolic response in a starch medium containing bromothymol blue were also evaluated. M1 showed pH 4.19 and 0.4 °Brix, whereas M2 showed pH 4.14 and 0.6 °Brix. Both samples exhibited cultivable growth. Bacillary and coccobacillary morphotypes, structures compatible with yeast cells, and a reaction consistent with catalase activity were observed in the cultured material. The starch-containing medium showed color changes compatible with pH modification. These data provide a baseline of the ferment for further studies with more fermentation units and molecular methods