Effects of Different Coating Materials on Quality of Microencapsulation Enzyme-assisted Aqueous Extraction Processing of Soybean Emulsion

In order to broaden the comprehensive application of enzyme-assisted aqueous extraction processing(EAEP)of soybean and effectively solve the problem of difficult demulsification,microcapsules of EAEP emulsion was prepared by spray dying. Emulsion activity,emulsion stability,particle size distribution,rheological properties,encapsulation efficiency,thermal stability and scanning electron microscopy were used to evaluate the effect of five composite coating materials on the microencapsulation of EAEP emulsion. Results showed that,before spray dying,the mixed emulsion with coating material CMC-MD had the highest viscosity of 39.18 mPa·s,with good emulsifying property. The particle size distribution shifted to the smaller particle size of 0.6~2.0 μm. The encapsulation efficiency of CMC-MD composite coating material was the highest,reached 90.3%,and the structural change initial temperature was the highest(98.3 ℃)with best thermal stability. According to scanning electron microscope(SEM)results,the microcapsules embedded in different coating materials exhibited regular spherical or ellipsoidal particles,and the particle diameters were different. The microcapsules with CMC-MD as the wall material had uniform size,compact structure and good embedding structure. The results illustrated that CMC-MD could be used as the coating material of EAEP emulsion microcapsules. The prepared microcapsules had good encapsulation efficiency,thermal stability and surface microstructure. It would have great significance for the development of EAEP emulsion processing applications and industrialization.