Rhodotorula glutinis 22P when co-cultivated with Lactobacillus helveticus 12A in a whey ultrafiltrate synthesizes maximum cell mass and carotenoid concentrations (31.9 g/l acid 8388 mu g/l, respectively) at 30 degrees C. The change in the growth temperature conditions of both cultures influences the carotenogenesis by yeast and the proportion of individual pigments forming up the carotenoids.