Abstract:

The preparation of sustained-release essence powder by microencapsulating liquid essence with gelatin and
sodium alginate as the coating materials using a complex coacervation method was optimized for improved embedding
rate using an orthogonal array design. It was demonstrated that the average embedding rate was 92.80% when the complex
coacervation was carried out at pH ranging from 4.0 to 4.5 using a coating material consisting of a 3:1 (by mass) mixture of 1%
gelatin and 0.5% sodium alginate with a ratio of wall material to core material of 1:1 (by mass). The ratio between the two
coating materials was found to be the factor with the greatest influence on embedding efficiency. Compared with ordinary
essence powder after extraction with petroleum ether, the microcapsule could be effectively released in a sustained manner.

Key words: liquid essence, microencapsulation, complex coacervation, gelatin, sodium alginate