Physico-chemical and microbiological quality changes in cocoa and whey protein enriched functional dairy drink during storage

Abstract

Cocoa and whey protein enriched functional dairy drink was subjected to storage studies at refrigeration temperature 4±1° C in the present study. The samples were studied for microbial and physicochemical tests during storage. The results in this study suggest that the product can be stored upto 18 days at 4±1° C. A decrease in pH from 7.01 to 6.49 for whey protein enriched product and from 6.94 to 6.41 in case of cocoa & whey protein enriched product was observed at the end of shelf life. The FFA increased from 0.72 to 1.46 meq./ml at the end of shelf life of 18 days in case of whey protein enriched product and from 1.16 to 2.02 meq./ml in case of cocoa & whey protein enriched product. An increase in the HMF content of the functional drink was recorded from 59.84 to 134.56 µ mol/l at the end of 18 days of storage in case of whey protein enriched product and from 1.16 to 2.02 µ mol/l in case of cocoa & whey protein enriched product. The total bacterial counts and yeast and mould counts were increased from 3.14 to 6.48 log cfu/ml and 1.14 to 2.10 log cfu/ml respectively in whey protein enriched functional drink. The coliform count was observed nil in both the variants of the functional dairy drink of throughout the storage period.