Some Physical Properties of Milk. III. Effects of Homogenization Pressures on the Viscosity of Whole Milk

Abstract

Data on effects of homogenization pressures from 15 to 3,500 p.s.i. on the viscosity of whole pasteurized milk at temperatures from 4° to 49° C. are reported. As homogenization pressures were increased above 300 p.s.i. there were highly significant linear increases in viscosity when measured at 9 temperatures. Pressures of 1,000, 1,500, 2,000, 3,000, and 3,500 p.s.i. increased viscosity as compared with the unhomogenized milk by respective averages of 7.1, 9.2, 11.9, 13.7, and 15.0%. Quadratic trends were also present. At pressures below 300 p.s.i. and temperatures above 23° C, linear trends were usually significant. At lower temperatures there were no significant linear or quadratic trends. Cubic trends sometimes indicated an increase in viscosity at pressures near 300 p.s.i. after a decrease beginning at pressures near 15 p.s.i. © 1956, American Dairy Science Association. All rights reserved.