KINETIC DEGRADATION AND STORAGE STABILITY OF β-CAROTENE ENCAPSULATED BY FREEZE-DRYING USING ALMOND GUM AND GUM ARABIC AS WALL MATERIALS

The purpose of this study was to evaluate almond gum as an encapsulation material for beta-carotene in comparison with gum arabic and to assess the functionality of the obtained powders applying them in cake as colorant. beta-carotene gum powders were prepared by freeze-drying, then the kinetic degradation as well as the surface color changes of the powders, during a storage period of 70 days, under three relative humidities (RHs): 10, 45 and 80% were studied. The degradation rate of beta-carotene and the decrease in the red color were described using a first-order kinetic model. The rate of degradation of beta-carotene as well as that of the red color increased as increasing RH until a value at which the samples collapsed (80% RH). Results showed that microencapsulation with almond gum offered greater protection to beta-carotene compared to gum arabic, and it was observed that the powders were able to color the studied food system (cake) in a homogenous manner.