Indigenous lactic acid bacteria in Idiazabal ewes' milk cheese

Three batches of Idiazabal cheese were studied at different production stag es. Counts obtained on three solid media (M17, MRS and MSE agar) showed gro wth during coagulation, pressing and brining operations and a decrease duri ng the two first months of ripening. While the pH and water activity decrea sed, dry matter and NaCl increased during ripening. Physiological and bioch emical characteristics of lactic acid bacteria were studied for their ident ification. Of the Lactococcus strains, 61% were identified as Lc. lactis su bsp. lactis biovar diacetylactis, 30% as Lc. lactis subsp. lactis, 7% as Lc . lactis subsp. cremoris and 2% Lc. raffinolactis. All Lactobacillus isolat ed from milk and curd and 19% of those isolated from cheese were identified as Lb. plantar um. The predominant Lactobacillus in cheese was Lb. casei s ubsp. casei (64%). Leueonostoc lactis was identified in cheese. (C) 1998 El sevier Science Ltd. All rights reserved.