FTIR Study of Hydration Phenomena in Protein-Sugar Systems

The hydration of gelatin-sugar systems was studied by Fourier transform infrared spectroscopy in the transmission mode using direct difference methodology. Information on the hydration kinetics of gelatin was obtained from the changes in intensities of the amide bands. Evidence of molecular interactions between the sugar and the carbonyl group of the protein was obtained from the results describing the hydration of the protein. Such interactions depended on both the concentration and the type of sugar present in the system. The effects of the presence of sugars on the kinetics of hydration of gelatin were interpreted in terms of selective hydration of the protein at low RH and specific molecular interactions between the gelatin and the sugar. The partitioning of water between the two components in the system was found to be an important feature in this study. Copyright 1998 Academic Press.