Effect of composition on moisture sorption of delactosed permeate

Delactosed permeate (DLP) is an effluent generated after the separation of most of the proteins and lactose from cheese whey. The inability to obtain stable products with acceptable low moisture content is one of the major drawbacks to further commercial development of DLP. To determine the factors influencing the sorption behavior, DLP samples from three different dairy processing industries were characterized for their composition and sorption behavior. Sorption data were successfully fitted to the Peleg model. The relationships among the compositional elements and Peleg constants for initial sorption rate (K1) and sorption capacity (K2) showed total sugar, lactic acid and mineral content had a significant influence on sorption. With an increase in the lactic acid and mineral content, the K1 and K2 values decreased, indicating higher initial sorption rate and higher sorption capacity.