Improvement in physical and thermal stability of cloudy ginkgo beverage during autoclave sterilization: Effects of microcrystalline cellulose and gellan gum

Abstract

This work aimed to apply microcrystalline cellulose (MCC) and gellan gum to improve the physical and thermal stability of cloudy ginkgo beverages. The stability of each beverage samples was characterized in terms of particle size, size distribution, zeta potential, rheological properties, Turbiscan Stability Index (TSI), and changes in backscattered light intensity (△BS). Our results indicate that an irreversible phase separation occurred in the beverage sample, induced by increased particle size, decreased zeta potential, and decreased viscosity during the sterilization process. Although the addition of either MCC or gellan improved beverage stability by decreasing particle size and increasing zeta potential, this improvement was limited; the aggregation and sedimentation of suspended particles still occurred, as revealed by large △BS and TSI changes. Beverage samples added with a mixture of MCC and gellan exhibited different physical and thermal stability values depending on the ratio of MCC to gellan. The addition of MCC (0.3%, w/w) combined with a small amount of gellan (0.05% or 0.08%, w/w) effectively prevented drastic thermal damage and improved physical and thermal beverage stability in comparison to MCC combined with the larger amount of gellan. This study provides some suggestions for the industrial production of cloudy beverages.