Effect of incorporation of denatured whey proteins on chemical compositionand functionality of pizza cheese

Denatured whey protein was added to cheesemilk prior to manufacture of pizz a cheese. Four concentrations of whey protein were used: 1. 0%-control; 2. 0.1%(w/w) whey protein; 3. 0.2% (w/w) whey protein; and 4. 0.4% (w/w) whey protein in the milk. Treatments 2 and 3 had no significant effect on the cheese compared to the control, but Treatment 4 was significantly different to the control in func tionality. The highest concentration of whey protein appeared to affect the structure of the curd to such a degree that in some cases the curd particles shattere d under the force of agitation. This resulted in the production of excessiv e fines, fat and protein losses. The moisture of the cheese of Treatment 4 was significantly higher, having a mean value of 53.6 % compared to the con trol (47.9 % moisture). The functionality testing revealed that the cheese with the highest concent ration of added whey protein was tough and fibrous, with poor melting and s tretching properties. In summary, the data show that denatured whey protein , at the higher concentration used, is not a suitable ingredient for pizza cheese, as it detrimentally affected the retention of fat and protein, and functionality, despite increasing the water-binding capacity of the cheese.