| Popis: |
Summary 1.The content of individual free fatty acids of pairs of raw and pasteurized milk Cheddar cheeses has been determined by a chromatographic method at intervals during the making and ripening periods. 2.In both raw and pasteurized milk cheese during the first 30 days of ripening, caproic, caprylic, and capric acids are absent, while n-butyric acid is present at slightly lower levels than those of the same cheeses at 420 days. Acetic acid levels for both types of cheese are approximately one half those of the same cheeses at 420 days. 3.Raw milk cheese at 420 days has considerably higher levels of n-butyric and acetic acids than corresponding pasteurized milk cheese. Caproic acid levels for the two types are quite similar. 4.Of the free fatty acids contributed by the milk, rennet extract, and starter culture used during cheesemaking, only the acetic and M-butyric acids of the milk are significant in amount. There is, however, negligible carryover of these acids into the finished cheese, since they can be accounted for completely in the whey at the time of dipping. 5.The action of intracellular bacterial lipases on the cheese fat is believed to be responsible for part of the free n-butyric and all of the free caproic, caprylic, and capric acids present in aged raw and pasteurized milk Cheddar cheese. |
