In this study, the effects of high pressure (HP) treatment on the mineral balance and pH of raw skimmed ovine milk were examined. HP treatment increased the level of non-sedimentable calcium and phosphate in ovine milk; such increases are probably the result of HP-induced solubilisation of micellar calcium phosphate. The HP-induced increases in the levels of non-sedimentable calcium and phosphorus were reversible on subsequent storage both at 5 and 20 degrees C for 4 or 24 h. As a result of HP-induced solubilisation of micellar calcium phosphate, an HP-induced increase in milk pH was observed, which was reversible on subsequent storage at 20 degrees C, but remained largely irreversible at 5 degrees C. HP treatment affected the mineral balance and pH of ovine milk in a manner analogous to that observed in bovine, buffalo and caprine milk, although there were considerable inter-species differences in the pressure at which specific effects occurred.