Use of Milk Protein Isolate to Improve the Textural Properties of Curd

Abstract

The objective of this study was to evaluate the effect of Milk Protein Isolate (MPI) on the textural properties of curd. Four different incorporation levels of MPI as 0.5%, 1%, 1.5% and 2% were compared with control having 2.5% of skim milk powder. Physicochemical properties including pH, titratable acidity, syneresis were measured during the shelf life of 14 days. Hardness, chewiness and adhesiveness were assessed as textural properties. Microbiological safety was analysed during the shelf life of 14 days including E-coli, yeast and mould counts. Sensory evaluation was carried out using 30 untrained panellists. All the textural properties were significantly different (p<0.05) among the treatments while the highest mean values were recorded in curd incorporated with 2% MPI. There was no significant difference (p>0.05) for pH and titratable acidity among the treatments. Curd developed with 2% MPI had the lowest syneresis compared to other treatments. Sensory evaluation results revealed that, appearance, texture and spoon ability were also much better in the 2% MPI treatment. Coliform was not observed during the storage period while yeast and mould growth were below the safe levels in all treatments during the period. In conclusion, 2% MPI could be effectively used to replace the skim milk powder like constituents in commercial curd manufacturing while enhancing both textural and nutritional properties and consumer acceptance.