Changes in water binding during ripening of cheeses made from raw, pasteurized or high-pressure-treated goat milk

The different types of water contained in the matrix of cheeses made from raw (RA), pasteurized (PA; 72degreesC, 15 s) or pressure-treated (PR; 500 MPa, 15 min, 20degreesC) goat milk were studied throughout ripening. Water content was qualitatively and quantitatively assessed by thermogravimetry. Thermogravimetric curves showed that water is lost in two successive steps (W-1 and W-2), depending on the temperature required for water to leave the cheese network. Although water content in W-1 and W-2 of all cheeses followed similar trends, decreasing towards the end of ripening, large relative decreases were observed in W-1. The highest decrease was observed in PA milk cheese, while PR milk cheese showed behavior similar to that made from RA milk. Differences in water binding could be attributable to changes in the cheese-matrix structure due to the technological treatment applied to milk, and/or physicochemical or biochemical differences (NaCl, proteolysis, lipolysis,...).