Heat and ethanol stabilities of high-pressure-treated bovine milk

Despite having well-documented effects on several constituents of milk, high pressure (HP) had little overall effect on the heat stability of raw, pre-heated or serum protein-free skim milk at pH values in the range 6.1-7.0. HP treatment at 600 MPa considerably increased the heat stability of concentrated skim milk at pH values > 6.7. The ethanol stability of raw skim milk was reduced by HP treatment, shifting the somewhat sigmoidal ethanol stability versus pH profile to more alkaline values; however, these changes were partially reversible during subsequent storage at 5degreesC for 24 h. Ethanol-mediated temperature-induced dissociation of casein micelles occurred in both untreated and HP-treated milk and was not dependent on storage of milk subsequent to HP treatment. These findings provide further insight into how the HP-induced changes in the constituents of milk influence milk properties. (C) 2003 Elsevier Ltd. All rights reserved.