Ripening and seasonal changes in microbial groups and in physico-chemical properties of the ewes' cheese Pecorino del Poro

Three batches of Pecorino del Poro, ewes' cheese made from raw milk, were examined throughout a 28-day ripening time at three different seasons. High logarithmic counts per gram of cheese for mesophilic coccal-shaped lactic acid bacteria (6.70-12.45), mesophilic lactobacilli (4.82-11.73), thermophilic coccal-shaped lactic acid bacteria (2.30-9.90), and thermophilic lactobacilli (2.95-8.15) were found. Coccal-shaped lactic acid bacteria were the dominant microorganisms throughout ripening. The microorganisms used as an indicator of hygiene during manufacture of the cheeses, coliforms and Escherichia coli, were considerably lower, as were enterococci and yeasts. Coliforms and E coli decreased sharply throughout ripening. Physico-chemical parameters such as pH (5.07-7.03), dry matter (46.34-72.79%), ether extract (31.35-51.84% of dry matter), crude protein (29.93-44.73% of dry matter), and chloride content (2.36-4.11% of dry matter) were also determined. Probably, the use of selected autochthonous mesophilic lactococci as a starter would control or suppress the growth of undesirable microorganisms. The results obtained suggest the need for improvements in milking and dairy conditions. (C) 2003 Elsevier Science Ltd. All rights reserved.