Yeast populations in Sardinian feta cheese

In this study, the yeast populations in feta cheese from two different Sard inian dairies were examined. Samples of good quality feta (32) and samples of feta with a slimy surface defect (10) were examined from Dairy A. Simila r, samples of good quality feta (23), feta with slimy surface defects (14) and samples with swelling defects (6) were examined from Dairy B. Kluyverom yces lactis was the dominating species in feta from Dairy A (95.2% of sampl es) followed by Debaryomyces hansenii (76.2%), Dekkera anomala (28.6%) and Dek. bruxellensis (19%). D. hansenii was dominant in samples from Dairy B ( 93%), followed by K. lactis (23.3%), Geotrichum candidum (23.3%) and Dek. a nomala (18.6%). No significant difference was observed between the occurren ce of yeast species in feta of good quality and in feta with slimy surface defects, thus confirming that slimy production is not associated with yeast contaminations. The swelling of samples observed in Dairy B seems to be ca used by Dek. anomala. In fact, this strong fermenting species was present i n all swelled samples in numbers exceeding 10(6) CFU g(-1), while it was is olated in very low concentration in only 5.4% of good samples. (C) 2001 Els evier Science B.V. All rights reserved.