Probiotic bacteria have been recognized as an important alternative to antibiotics and other growth factors used in animals, which have a negative influence on animal and consumer’s health. Preliminar experiments were performed in shaker to obtain the media formulation and the growth kinetics for isolated strains of Lactobacillus spp. and Bifidobacterium spp. Experiments on a 2.7 L batch reactor allowed the study of operation parameters as agitation and aeration, obtaining the highest growth using two 6-paddle Rushton turbines and air flow of 1.4 WM. These results were used to scale-up the batch process to a 50.0 L bioreactor, obtaining a geometrically similar design that produces a cell density of 6.5 g/L in 24 hours of operation, with optimum media and operating conditions, broadening the field of application of probiotics to industries not necessarily related to dairy products.