| Abstract
| - 1H NMR signal was used to characterize highly hydrated milk protein dispersions (3−20% dry matter)with various micellar casein concentrations (3−15%), whey protein concentrations (0−3%), lactoseconcentrations (0−7.5%), CaCl2 concentrations (0−2 mM), and pH (6.2−6.6). The results showedthe predominant effect of micellar casein concentration on water state and were consistent with thethree-site relaxation model in the absence of lactose. The relaxation rates observed for thesedispersions were explained by the free water relaxation rate, the hydration water relaxation rate, andthe exchangeable proton relaxation rate. Hydration water was found to be mainly influenced by caseinmicelle concentration and structure. The variations in hydration with pH were consistent with thoseobserved for classical measurement of voluminosity observed at this range of pH. The effects oflactose and whey protein content are discussed. Keywords: Casein; lactose; hydration water; NMR relaxation; pH effect
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