The search of a microorganism with the ability to produce the enzyme beta-galactosidase was undertaken according with the requirements of the market, in economical, technological and sanitary terms. The process consisted of recovery and use of the effluent from milk and cheese used to feed pigs, producing at the same time different types of contamination; once investigated and adjusted the technological variables to produce the enzyme, and selected the most convenient microorganism for such purpose the acting upon the extraction, conservation and purification of the product were adjusted. Comparative results of conversion were obtained with different test, at laboratory scale and industrial plants, in similar conditions to those obtained with importation products.