Studies on Keeping Quality of Semisoft White Mould Cheese Ripened by Penicillium caseicolum

Abstract

The keeping quality of semisoft white mould cheese ripened by Pen. caseicolum was tested. The result of organoleptic test showed that the cheese did not keep for over a week at room temperature (20°C) and for over a month at cold storage temperature (2°C).
In order to improve the keeping quality of the cheese, its samples were canned and sterilized at 100°C for 30 minutes and at 115°C for 6 minutes. The effects of these two sterilization methods on texture, flavor, pH and nitrogen distribution (total water soluble N, total water soluble protein N, proteose-peptone N, ammonia N, tyrosine and glutamic acid) were almost the same. But their effects on the keeping quality of the canned cheese were to a certain extent different, that is, the former sterilization method could keep the quality of the canned cheese palatable for 2 months, while the latter could do for 4 months.
The keeping quality of the cheese, which was stored for 3 months at frozen temperature (-20°C) and then defrosted, was tested also.
Changes in the texture, flavor, pH and nitrogen distribution of the cheese during canning process and storage were discussed.