Monitoring of water ordering in aqueous protein systems

Method of waveguide dielectric resonance, a variation of the microwave (millimeter) spectroscopic technique, was applied for monitoring of protein transformations via measurements of the overall water ordering in the hydration shells of protein groups. This effect was evaluated as a quantity of bound H2O molecules, which rotational mobility was lost owing to the presence of solute in water. Increase in specific bound water for chemical acidification of casein micelles and cold gelation of denatured whey proteins was several times smaller than contribution to hydrophobic hydration of ethanol.