Effects of formulations on Gac oil emulsion stability for microencapsulation

The objective of this study was to determine the most suitable formulations for a high stability Gac oil emulsion and a high retention within the oil of lycopene and β-carotene contents. We investigated the effects (i) of the concentration of the wall materials (WPC/GA, 7/3, w/w) (20, 30 and 40%, w/w), (ii) the ratios of Gac oil to wall material (2:1, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7 and 1:8, w/w) on the emulsion stability and retention of lycopene and β-carotene contents at different storage temperatures (4, 22 and 37 °C), as well as on viscosity, pH, mean particle size and particle size distribution. Results showed that emulsions obtained using the ratios of 1:5 up to 2:1 and a concentration of 30% remained highly stable for at least 24 h at the storage temperatures. Among these samples, the retention of carotenoids in the emulsions formulated with the ratios of 1:3, 1:4, and 1:5 was found to be the highest. At those formulations, emulsions had viscosity of < 30 cP, mean particle size of < 10 μm and pH of 5.7 to 5.8. It is concluded that emulsions with excellent stability, low viscosity, and small and uniform particle sizes can be formulated for microencapsulation