Preparation Process Optimization and Quality Analysis of Litsea pungens Hemsl Essential Oil Microcapsules

The essential oil of Litsea pungens Hemsl was used as the main raw material, and the method of vacuum freeze-drying was used to prepare the microcapsules of essential oil of Litsea pungens Hemsl, and the embedding rate of the microcapsules was used as an index. Optimizing the microcapsule embedding process of essential oils to determine the best process parameters. At the same time, the physical and chemical properties, microstructure, volatile rate and peroxide value of essential oil were analyzed during storage. The results showed that the best parameters of the microcapsules of essential oil were as follows: Composite wall material ratio (soy protein isolate: β-cyclodextrin) was 1:1 (g/g), core wall material ratio was 1:5(g/g), solid content was 15%, emulsifier content was 3%, emulsifier ratio was 1:4 (g/g), emulsifying temperature was 40 ℃, embedding rate of the microcapsules was 84.68%, its water content, solubility and bulk density were 3.05%, 91.04% and 0.35 g/cm³, respectively. The results of SEM showed that the microcapsules of Litsea pungens Hemsl essential oil were irregular in shape. With the extension of storage time, the volatilization rate and peroxide value of microcapsules of Litsea pungens Hemsl essential oil were lower than those of essential oil, which indicated that the microencapsulation of Litsea pungens Hemsl essential oil could effectively slow down the volatilization rate and reduce oxidation degree of essential oil.