RECRYSTALLIZATION IN AQUEOUS FRUCTOSE SOLUTIONS AS AFFECTED BY LOCUSTBEAN GUM

Rates of ice recrystallization were measured in aqueous fructose solut ions containing locust bean gum (LBG). The effects of temperature, ice phase volume and LBG concentration were determined. Decreasing temper ature reduced the recrystallization rate: the dependency followed Will iams Landell Ferry kinetics. An increase in ice phase volume resulted in an increase in the recrystallization rate. Addition of LBG reduced the recrystallization rate up to a concentration of 0.3% (w/w); furthe r addition resulted in no further decrease. The hypothesized mechanism of action of LBG is via weak adsorption of the polysaccharide to the ice crystal. Freeze concentrated solution viscosity did not correlate with observed recrystallization rates.