(52 g L−1) and productivity (4.5 g L−1h−1) in continuous concentrated
whey (15% substrate) fermentation, as compared to immobilized K.
fragilis cells (ethanol titre of 13 g L−1 and productivity of 1.1 g L−1h−1)
(Tables 1 and 2). A similar biocatalyst has been applied in a hybrid
system coupling whey fermentation with a pervaporation module for
ethanol separation (Lewandowska and Kujawski, 2007; Staniszewski
et al., 2009). Rosenberg et al. (1995) used permeabilized K. marxianus
cells as the source of ß-galactosidase for simultaneous hydrolysis of
lactose in concentratedwhey and fermentation by S. cerevisiae, obtaining
enhanced ethanol productivity as compared to direct fermentation using
K. marxianus (see Tables 1 and 2).