The Effect of Whey Protein Isolates, Sodium Caseinate and Carboxymethyl Celloluse on Sensory and Oscillatory Rheological Properties of Salad Dressing

In this research, the effects of three variables, whey protein concentrate, WPC (0.7- 2.8%), sodium Ceinate, SC (0.7-208%) as a substitute for egg and carboxymethyl cellulose, CMC (0.66-0.234 % w/w) as thickening agent on sensory (taste and texture) and rheological (Complex viscosity, η*, Storage modulus, G´ and Loss modulus, G˝) properties of salad dressing were investigated. The central composite experimental design (CCD) was used and the data were analyzed using response surface methodology (RSM). The results of analysis of variance (ANOVA) showed that P values of all models were significant and lack of fit P values was no significant at the level of 95%. Therefore, the adequacy of models was acceptable. The results showed that the optimum level of hydrocolloids for producing salad dressing with highest rheological properties were 2.27% WPC, 2.27% SC and 0.2341% CMC. The sensory evaluation of six treatments with improved physicochemical properties and stability of salad dressing (data not shown) and control sample (prepared with eggs) was carried out. The results suggest that there is no significant difference in the overall acceptability between control samples and samples prepared with the alternatives. So milk proteins can be used as a suitable substitute for egg in the salad dressing.