Whey in Cultivating Lactose-Fermenting Yeasts

Whey processing is unavoidable in sustainable production. Waste whey can be utilized in the biotechnological production of lactose-fermenting yeasts. This study featured cultivation patterns of separate, combined, and hybridized cultivation of Kluyveromyces yeasts in cheese and curd whey. The fastest growth and greatest biomass accumulation belonged to K. marxianus 459 in cheese whey (≤lgN 9 after 24 h and lgN 9.8 after 48 h of cultivation). K. marxianus 459 and 1338 adapted more quickly in curd whey than in cheese whey, with the opposite result for K. lactis 1339. Hybrid strains of K. lactis 1333 × K. marxianus 1338 and K. lactis 1333 × 1339 demonstrated a higher growth rate than individual strains over 24 h in both types of whey. The difference in lgN values was 7.6–31 %, depending on the whey type and strain. The most active formation of volatile components was observed in the experiments that featured co-cultivation of K. lactis 1333 + K. marxianus 1338 in curd and cheese whey. In this study, co-cultivation and hybridization (both interstrain and interspecies) of some lactose-fermenting yeasts changed their biochemical and physiological properties, which was consistent with other studies. The obtained results can be used in the production of β-galactosidases for the biosynthesis of prebiotic oligosaccharides.