Diffusion of Aqueous Sugar Solutions as Affected by Locust Bean Gum Studied by NMR

Abstract

ABSTRACTTime domain proton NMR was used to study translational diffusion and molecular mobility of sugar and water molecules in simple aqueous solutions to determine how the addition of hydrocolloid stabilizers affect their mobility. Results showed that addition of Locust Bean Gum (LBG) did not affect the diffusion or mobility of either the sugar or water molecules over distances up to 10μm 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 growth 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 of the local interfacial region between the ice crystal surface and the surrounding unfrozen solution.