EFFECT OF INCORPORATING WHEY PROTEIN HYDROLYSATE ON PROCESSED CHEESE SPREAD QUALITY

Abstract

Five processed cheese spread treatments were made to investigate the effect of incorporating whey protein hydrolysate on the quality attributes of resultant processed cheese spread. Whey protein hydrolysate was incorporated at the rate of 2.5, 5.0, 7.5 and 10% instead of fresh Ras cheese that used to making control processed cheese spread. The resultant processed cheese treatments were stored for 3 months at 6 ± 2 Cᵒ. The obtained results revealed that incorporation of whey protein hydrolysate caused a slight increase in pH values, total protein, soluble protein contents and meltability of cheese, while caused a significant reduction in oil separation index, ash content and titratable acidity changes were proportional to the rate of whey protein hydrolysate substitution. Incorporation of whey protein hydrolysate decreased the whiteness of processed cheese spread treatments, while increased the values of a, b and ∆E (change in colour). Adding whey protein hydrolysate increased hardness, adhesiveness, cohesiveness and springiness of the resulting processed cheese spread treatments, while decreased the values of gumminess and chewiness. Incorporating whey protein hydrolysate up to 5.0% did not affect significantly the acceptability and organoleptic scores, while increasing the ratio of adding whey protein hydrolysate above 5.0% caused a significant decrease in the organoleptic scores of resultant processed cheese spread. Titratable acidity, total protein content and oil separation of processed cheese spread treatments were slightly increased during storage period, while pH values, meltability and moisture content decreased.