Effects of emulsifying conditions on creaming effect, mechanical properties and microstructure of processed cheese using a rapid visco-analyzer.

The creaming effects, mechanical properties and microstructures of processed cheeses were investigated under different emulsifying conditions using a rapid visco-analyzer, and the changes in protein network related to the creaming effect and the occurrence of yielding points were discussed. The higher stirring speed affected the fat globules to be smaller, and gave the processed cheese more firmness at fixed stirring time. The longer stirring time caused the protein network to become fine-stranded. A fine-stranded structure promoted the creaming effect, and hence the formation of yielding point in the mechanical properties. The emulsifying salts had active effects on the creaming effect and mechanical properties at longer stirring time. The fine-stranded structures were shown in the cases of a binary mixture of polyphosphate and disodium phosphate (PDSP), polyphosphate (PP), and trisodium citrate (TSC). Monophosphate (MP) showed the lowest ability to alter the protein network, but was assisted at the higher stirring speed.

Effects of pre-cooked cheeses of different emulsifying conditions on mechanical properties and microstructure of processed cheese.

The effect of pre-cooked cheeses of different emulsifying conditions on the viscosities, mechanical properties, fat globules, and microstructure of processed cheese was investigated, and changes in protein network relating to the creaming effect and the occurrence of yielding point were discussed. The addition of pre-cooked cheeses with a short stirring time had no obvious impact on the fat globules and protein network. The random network brought low viscosities and a gradual increase in the fracture stress/strain curve. The addition of pre-cooked cheeses with the long stirring time caused protein network to become fine-stranded. The fine-stranded network caused creaming effect, and brought yielding points in the mechanical properties. The pre-cooked cheese with the small fat globules also caused fat globules to become smaller, and give the processed cheese more firmness. This study provides a potential solution to control the functional properties of processed cheese by using a variety of pre-cooked cheeses.