Influence of Temperature and pH on the Solubility of αs1-, β- and κ-Casein

Abstract

Both temperature and pH affect the solubility of κ-casein and β-casein in the region of their isoelectric points. This investigation covered a range of from 3.9 to 5.2 pH. From pH 4.7 to pH 5.2, κ-casein became more soluble as the temperature was decreased. However, temperature had no effect on the solubility of κ-casein between pH 3.9 and 4.6. The solubility of α-casein increased as the temperature decreased over the entire range of pH 3.9 to 5.2. The increased solubility of β-casein was greatest between 5 and 15 C. Solubility of αs1-casein was affected by temperature to a minor extent; αs1-casein solubility was slightly greater at 5 C than at 25 C at pH values below 4.0 and above 5.0. © 1971, American Dairy Science Association. All rights reserved.