Influence of storage temperatures on the quality of concentrated whey

There is an increasing interest in the use of whey due to its therapeutic and functional properties such as water binding,solubility,gelation,emulsification and foaming. whey and its components are being incorporated as value-added ingredients in many foods including dairy,infant formulas,sports foods,meat,bakery,beverages and other food products. whey is highly perishable due to high water activity. this project was designed to develop concentrated whey by an economical evaporation method,and then its quality was evaluated at freezing (-20°c) and refrigerated (4°c) storage temperatures. the results showed that during frozen storage minor changes occurred in ph (4.22-4.12),acidity (2.63-2.72%),total solid (48.68- 47.82%) and lactose contents (36.81-36.02%) as compared to the decrease in ph (4.22-3.81),acidity (2.63-2.93%),total solids (48.68-44.30%) and lactose (36.81-33.87%) contents at refrigeration storage. an increase in viscosity and npn content were observed at both temperatures which might be due to protein denaturation. the protein (4.53%),ash (4.03%) and fat (2.33%) remained constant. the sds-page patterns indicated a significant denaturation and aggregation of major whey proteins during storage which was intense at freezing temperature. © 2015 university of agriculture. all rights reserved.