Estudo da vida útil de queijo Minas

The shelf life of the Minas fresh cheese was evaluated during 30 days of storage at 4 °C through microbiological and physical-chemical analyses. Three lots (A, B, and C) of the same brand and from the same dairy were analyzed on days 1, 10, 20, and 30 after production. The counting of the colonies of psicrotrophic microorganisms, lypolitics, proteolytics, lactic acid bacteria and mesophilic bacteria showed a continuous growth reaching 8.50, 8.04, 8.30, 6.05 and 7.7 log UFC.g-1, respectively. The Escherichia coli colony grew in one of the lots studied, and Staphylococcus coagulase + and Salmonella were not detected. In the same period, there was reduction of pH (0.81) and the increase of the lactic acid (0.026%). No cheese fat decrease was observed (21.5%) although the amount of free fat acid increased in 0.22 mg KOH/g of fat. The protein varied from 21.30% to 22.10%, which is not a significant difference. The proteolysis extension index increased 3% every 10 days. On the 30th day, the sample of the lot C proved improper for the consumption with 1.7 x 104 NMP.g-1 de E. coli.