Changes in the Functionality of Dry Whey Protein Concentrate During Storage

Various functional properties (protein solubility, foam stability, emulsifying capability) and development of browning of dry whey protein concentrate containing 52% protein were monitored during 6 mo at temperatures ranging from -40 to 400C and water activities ranging from .15 to .41. Of the product attributes studied, increases in browning were most, important. Of the storage variables studied, storage temperature and time were most important and water activity was of secondary importance. To achieve good retention of the initial attributes of WPC during 6-mo storage, the temperature should be no higher than 20C and the water activity should not exceed about .2.