Abstract:In this study， glyceryl monostearate （GMS） and sodium starch octenyl succinate （SSO） were used as wall materials to embed the core material of L-menthol. Thermo-sensitive L-menthol microcapsules were prepared by spray freeze drying. The preparation process of thermo-sensitive L-menthol microcapsules was optimized through single-factor experiments and response surface experiments. The optimal process conditions were solid content of 21%， GMS/SSO mass ratio of 0.16， core material/wall material mass ratio of 0.19， homogenization pressure of 30 MPa， feeding speed of 15 mL/min， and drying temperature of 42 ℃. Under these conditions， the embedding rate of thermo-sensitive L-menthol microcapsules could reach 91.89%. The morphology and properties of the microcapsules were observed with scanning electron microscopy， laser particle size analyzer， and thermogravimetric analyzer. The results showed that the microcapsules had a complete microstructure， a spherical shape， no adhesion， good particle dispersion， and an average particle size of 1.9 μm.The mass fraction of L-menthol rapidly decreased at 153 ℃， and the thermo-sensitive L-menthol microcapsules exhibited relatively good release property at 75 ℃.