Kluyveromyces lactis was cultured in cheese whey permeate on both batch and continuous mode to investigate the effect of time course and growth rate on β-galactosidase activity, lactose consumption, ethanol production and protein profiles of the cells. Cheese whey was the substrate to grow K. lactis as a batch or continuous culture. In order to precise the specific growth rate for maximum β‐galactosidase activi...