Effect of pedoclimatic conditions on the physico-chemical characteristics, hygiene and coagulation properties of milk for Parmigiano-Reggiano cheese

The aim of this study was to compare the quality of milk produced in different pedoclimatic zones (hill and plain) destined to the production of Parmigiano-Reggiano cheese. The study was carried out on 4,996 herd milk samples (1,464 from 53 herds located in hill areas and 3,532 from 97 herds located in the plains) collected in the province of Reggio Emilia. The following parameters were determined for each milk sample: fat, protein, titratable acidity, total bacterial count, somatic cells, coliforms bacteria, Clostridia spores and rennet coagulation properties. Milk produced by hill herds was characterized by higher fat content (3.51 vs 3.47 g/100g; P <= 0.05) and lower total bacterial count (58,242 vs 66,833 CFU/mL; P <= 0.001), somatic cells (285,369 vs 309,660 cells/mL; P <= 0.01) and coliforms bacteria (1,198 vs 1,334 CFU/mL; P <= 0.001) compared to milk produced in plain herds. Moreover, milk produced in hill herds showed a lower percent of samples with anomalous coagulation attitude (0.13 vs 0.68%; P <= 0.05) and a lower rate of samples contaminated by Clostridia spores (16.05 vs 19.71%; P <= 0.01) than milk produced in plain herds.