Abstract:

Chitosan and maltodextrin were used as wall materials to prepare vitamin E microcapsules by spray drying. The encapsulation efficiency and retention ratio of vitamin E and the moisture content of microcapsules were 89.02%, 91.73% and 2.67%, respectively. Fine surface and internal structure of microcapsules were observed under scanning electron microscopy (SEM). The values of Tg and Tm of microencapsulated vitamin E were determined by DSC to be 41.579 ℃ and 199.483 ℃, respectively, indicating good storage stability and broad application range. In addition, the retention ratio of microencapsulated vitamin E was measured at different relative humidity and modeled as a function of storage temperature using Avrami’s equation. Results showed that releasing rate of vitamin E at 75% relative humidity was even faster than that at 32% or 50%.

Key words: vitamin E, microencapsulation, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), release