Diffusion of aqueous sugar solutions as affected by locust bean gum studied by NMR

Time domain proton NMR was used to study translational diffusion and molecu lar mobility of sugar and water molecules in simple aqueous solutions to de termine how the addition of hydrocolloid stabilizers affect their mobility. Results showed that addition of Locust Bean Gum (LBG) did not affect the d iffusion or mobility of either the sugar or water molecules over distances up to 10 mu m in unfrozen solutions. The diffusion properties of the sugar and water molecules were not affected by either biopolymer cryogelation or the presence of ice. We hypothesized that retardation of the ice crystal gr owth rates in aqueous sugar solutions caused by the presence of LBG was not a bulk property of the solution. The most likely cause is a modification o f the local interfacial region between the ice crystal surface and the surr ounding unfrozen solution.