Inhibition mechanisms of ice crystal recrystallization by polysaccharides: a comparative analysis of molecular structures and cryoprotective properties.

Background: Polysaccharides are increasingly being recognized as promising food-grade cryoprotectants due to their broad availability and health benefits. However, their practical application is hindered by limited ice recrystallization inhibition (IRI) activity. The purpose of this study was to compare the IRI activity of several natural polysaccharides.

Results: We conducted a comparative analysis of molecular structures and cryoprotective properties using various physicochemical and structural characterization techniques. Among the polysaccharides studied, locust bean gum exhibited the highest IRI activity at 10 mg mL^-1, with mean largest grain size values of 51.5 μm. Inulin, citrus peel pectin, and locust bean gum demonstrated gradually increasing IRI activity as the concentration of the solution increased. This was likely due to enhanced formation of intermolecular networks that raised viscosity and created physical barriers that limited ice crystal growth. The correlation analysis revealed a significant negative correlation between the mean largest grain size of polysaccharides at a concentration of 1 mg mL^-1 and 50% relative humidity. Melting temperature was significantly negatively correlated with OH, CO, and COC, further confirming that the ability of polysaccharides to inhibit ice crystal growth is related to specific functional groups, relative humidity, and melting temperature.

Conclusion: The findings offer insights into the potential of polysaccharides to serve as effective natural cryoprotectants, improving the stability and texture of frozen foods. © 2025 Society of Chemical Industry.