Effect of wall materials and core oil on the formation and properties of styralyl acetate microcapsules prepared by complex coacervation

Styralyl acetate (SA) was encapsulated in gelatin and gum Arabic using complex coacervation. The response surface methodology was carried out to explore effects of wall concentration and the amount of SA on the yield, encapsulation efficiency, and oil loading capacity and to optimize the process conditions. The results of optimization showed that the wall concentration of 1.35 % (w/v) and the SA of 2.23 g were used, the highest yield of 72.8 %, encapsulation efficiency of 80.6 % and oil loading capacity of 66.2 % were obtained. The morphologies were observed by an optical microscope and scanning electron microscopy (SEM), respectively. Microcapsules exhibited excellent thermal stability than SA by thermogravimetric analysis (TGA). Moreover, Fourier transform infrared and X-ray diffraction examined structure changes of wall materials and core oil.