Evolution of water structure in biopolymer solutions during the gelation process

The evolution of water structure in train of gelation process is examined in aqueous solution of gelatin using Raman spectroscopy of the O-H stretching band. The measurements have been performed at room temperature for four concentrations of gelatin, which yields different dimensions of nanopores in the network of the created gel. We have found that during the sol-gel transition the number of molecules that participate in the regular tetrahedral H-bond structure increases, and the effect is stronger for higher concentration of the biopolymer. (C) 2004 Published by Elsevier B.V.