Abstract

An application of the co-culture of Kluyveromyces marxianus and Saccharomyces cerevisiae for ethanol production from deproteinized cheese whey was established. Among several co-cultures examined, the co-culture of S. cerevisiae UFLA KFG33(ethanol over-producer) and K. marxianus (UFLA KF22) showed the highest value of ethanol production (16.02±0.11 g L^-1) and the highest yield of ethanol by fermentation time (0.22±0.05 g L h^-1), according to Qp (volumetric productivity). These yeasts also showed the highest value of cell mass concentration in final fermentation (1.02±0.01 g L^-1). The co-cultures were performed in 72 h fermentation at 28°C with shaking at 100 rpm. The results indicate that this methodology is a promising technique for the production of ethanol using deproteinized cheese whey.

Key words: Yeasts, Rep-PCR, lactose fermentation, whey.