Microbiological study of Manura, a hard cheese made from raw ovine milk in the Greek island Sifnos

Changes in the microbial flora of Manura, a raw ovine milk cheese, were studied during ripening. In general, the various microbial groups developed better on the cheese surface than in the interior, but red wine treatment had an inhibitory effect on their growth and microbial counts decreased (P < 0.05) more rapidly on the cheese surface than in the interior. NaCl and moisture of the cheese affected microbial levels significantly. Thus, Enterobacteriaceae and coliforms were reduced sharply (P < 0.05) during ripening on a straw bed (∼3 months) and they were not detected in mature cheese. Lactic acid bacteria predominated over the other microbial groups throughout ripening. Leuconostoc mesenteroides ssp. cremoris, Pediococcus pentosaceus and Lactobacillus paracasei ssp. paracasei, frequently found in maturing cheese, could be used as starters to make this cheese. Moreover, the lactic acid bacteria predominating in mature cheese, such as Weissella paramesenteroides, Lactobacillus bifermentans and Lactobacillus brevis, may contribute to cheese ripening through their biochemical activities.