Abstract: Vanilla essence oil microcapsules were prepared with jackfruit seed starch as the shell material by four physical methods including saturated water solution method (SWSM), paste method (PM), ultrasonic method (UM), and spray-drying method (SDM). They were comparatively evaluated in terms of product yield, microencapsulation efficiency, loading, slow release capacity, storage stability and other physicochemical properties. The data we obtained showed that product yields range from 74.34% to 92.06%, microencapsulation efficiencies ranged from 68.90% to 74.49%, and loadings varied between 21.27% and 26.71%. SDM showed the maximum yield (92.06%) and microencapsulation efficiency (74.49%) among the four methods, while the minimum yield and microencapsulation efficiency of 74.34% and 68.90%, respectively were obtained by PM. Fourier transform infrared spectroscopy results showed that vanilla essence oil could be embedded by the four methods successfully. All four microcapsules showed no significant color differences and were uniformly spherical in shape. The microcapsules prepared by SDM showed the biggest particle size (around 600 nm), whereas those prepared by SWSM exhibited the smallest particle size (around 200 nm). The SDM microcapsules showed the best thermal stability but the lowest slow-releasing potential and storage stability, and the retention rate of vanillin and peroxide value were 49.11% and 14.24 mmol/kg after 50 and 15 days of storage, respectively. Overall, compared to the other three methods, SWSM was the best method for preparing vanilla essence oil microcapsules.

Key words: physical method, microencapsulation, jackfruit seed starch, vanilla essence oil