Effect of high-temperature treatment of milk and whey protein denaturation on the properties of rennet–curd cheese: A review

Abstract

High temperature treatment of milk (HTT) at temperatures (e.g., 75–100 °C for 1–10 min) higher than those used in conventional pasteurisation (72 °C for 15–30 s) has been used in the manufacture of rennet-curd cheeses to increase the recovery of whey protein, enhance cheese yield, and/or improve the texture of reduced-fat cheese. HTT results in denaturation and interaction of denatured whey proteins with κ-casein. The denatured whey protein/κ-casein complexes remain with the para-κ-casein micelle following rennet hydrolysis, and impede its fusion during gelation and syneresis of the resultant curd, to a degree that increases with severity of HTT. Consequently, cheese from HTT-milk has higher contents of moisture and denatured whey protein, is softer, and has inferior melting properties on baking or grilling. The effects of HTT can be partially mitigated by alteration of cheesemaking parameters to normalise cheese composition, and/or addition of exogenous proteinases to improve melting properties.