Effect of milk pretreatment on the whey composition and whey powder functionality

Changes in cheese production processes may have a significant effect on subsequent whey composition and functionality. To control these changes is important since whey is commonly processed into ingredients used in numerous applications in the food industry. In this study, the characteristics of 4 demineralized whey powders (DWPs) were studied. DWPs were produced from partially high-temperature heat-treated (HH), ultrafiltered (UF), or ultrafiltered high-temperature heat-treated (UFHH) milk. DWP produced from pasteurized milk was used as a reference (REF). All experiments were carried out on industrial scale. The quantity of nonprotein nitrogen (NPN) in total protein (TP) was elevated by HH, and reduced by UF treatment. Whey protein content of whey was significantly elevated by UF, but reduced when HH treatment was applied. The volume and total solids of UFHH whey were significantly reduced compared to REF and HH wheys, but the chemical composition was comparable. There were no significant differences in the degree of denaturation, viscosity, water-binding capacity, emulsifying capacity, or emulsion stability of the DWPs, but heat stability was significantly elevated by UF treatment.