Milk refrigeration and quality of Parmigiano-Reggiano cheese: characteristics of vat milk.

摘要

The aim of the research was to study the effect of the storage temperature on vat milk quality in Parmigiano-Reggiano cheese manufacture. Six Parmigiano-Reggiano cheesemaking trials were performed. For each trial, the whole herd milk production was divided into two tanks: in the first one the milk was stored at 4-6 degrees C (TS) and in the second one the milk was stored at 20 degrees C (TC). In the cheese factory, TS and TC milk were processed separately and in parallel to Parmigiano-Reggiano cheese. A vat milk sample was collected prior each cheesemaking. On every vat milk sample the following analysis were carried out: crude protein, casein, casein number, paracasein, paracasein number, dry matter, ash, fat, rennet-coagulation properties, pH and titratable acidity. TS milk showed an higher fat content (2,49 vs 2,43 g/100 g) and a lower crude protein (3,24 vs 3,26 g/100 g) and paracasein (2,32 vs 2,35 g/100 g) content than TC milk. The fat to casein ratio resulted higher in TS milk (0,99 vs 0,96), on the contrary paracasein number and ash content resulted higher in TC milk (71,47 vs 71,95% e 0,70 vs 0,71 g/100 g) than TS milk.