Comportamiento sibmiótico del kéfir de leche utilizando como sustrato el germen de soya.

Abstract

The objective of this study was to analyze the symbiotic behavior of milk kefir using soybean germ (Glycine max) as substrate. Germination was performed using the glass jar method for 4 days. Subsequently, the soluble extract was obtained from the soybean germ with a 1:3 ratio (soybean grain: water). Three percent of the kefir grains (activated) were inoculated with the soluble extract of the sprout. The soluble extract of the soybean sprout had a total sugar content of 5.57% and fermentable carbohydrates of 3.37 g/L (sucrose), which served as a reserve source. In addition, lipids with 1.40% were used in the catabolic activities of the grain, while proteins increased the soluble nitrogen of the legume with 6.66%. The beverage had a pH of 6.67 and an acidity of 0.17% lactic acid. The microbial population count of the soluble extract of the kefir soybean sprout reached its logarithmic development phase at 24 hours in lactic acid bacteria, at 48 hours in acetic acid bacteria and yeasts, consuming the nutrients present in the beverage. The products of their metabolism influence the pH present in the medium. The phase of decline in lactic acid bacteria, acetic acid bacteria and yeasts was at 72 hours, with a medium deficient in nutrients. The symbiotic activity of milk kefir using the germinated soluble extract was mutualistic, since the microorganisms present cooperated for growth, with favorable pH and acidity changes, nutrient consumption and the creation of a suitable environment. It is recommended to supplement the beverage with fruits or vegetables that present a considerable amount of sugars to improve the substrate.