Influence of Pressurization on Goat Milk and Cheese Composition and Yield

摘要

Fresh goat cheese was made from pasteurized (72 deg C, 15 s) or HP-treated milk (500 MPa, 15 min, 20 deg C). Microbiological quality (i.e. mesophilic aerobic bacteria and enterobacteria) of pressurized milk was comparable to pasteurized milk. Pasteurized and HP-treated milks had different pHs and non-casein nitrogen. During the curd formation, the pH fell faster in pasteurized milk than in HP-treated milk and there was a slightly larger amount of milk fat separated from the curd whey in HP-treated milk. HP treatment reduced the level of whey expelled from the curd making the whey removal process more difficult, and so the time involved in the cheesemaking was increased. The cheese made from HP-treated milk had higher levels of moisture and salt, but a slightly lower fat content than pasteurized milk. Additional retention of whey protein and, especially, the greater moisture led to improvements in cheese yield from HP-treated milk.