This study is part of research developed in the area of ​​Food Science, Department of Analytical Chemistry and Food, University of Vigo Ourense Campus, Spain.; whose ultimate goal is to occurring fermented beverages with probiotic properties with kefir grains juice of red and white grapes would thus not valuing vinificables grapes with low commercial value or direct consumption. And obtaining healthy drinks combining ink effects mainly polyphenol grape character with antioxidant kefir and functional benefits. Kinetics main fermentation process cash studied, the effect of change on the fermentation substrate and microbial populations analyzed kefir. The procedure was carried out as follows: the pellet was activated, conducted a sequence of four successive crops. In each one the juice grain was incubated of nonsterile red grape during 24 h. The grain separated and juice fermented by fr...