微胶囊化脂肪酶型TTI的制备及其性能研究

针对脂肪酶在时间-温度指示剂的应用中存在热稳定性能差，温度、pH值对其活性影响较大等问题，采用离子凝胶技术制备脂肪酶微胶囊。应用单因素试验和正交试验相结合的方法，以海藻酸钠、壳聚糖、氯化钙浓度为变量，优化脂肪酶微胶囊的制备工艺，对原脂肪酶与脂肪酶微胶囊的热稳定性能、最适温度与pH值进行研究，采用红外光谱(FTIR)、扫描电镜(SEM)对脂肪酶微胶囊结构及形貌进行分析，并对脂肪酶微胶囊在时间-温度指示剂中的应用做出初步研究。得到了脂肪酶微胶囊最佳制备工艺条件为：海藻酸钠质量浓度30 g/L，壳聚糖质量浓度6 g/L，氯化钙浓度0.3 mol/L。脂肪酶微胶囊的热稳定性比原脂肪酶有明显提高。脂肪酶微胶囊制备工艺稳定、可靠，具有应用于时间-温度指示剂中的实用价值。

Preparation and Properties of Microencapsulated Lipase TTIs

Lipase microcapsules were prepared by adopting ion gel technology in order to solve the problems of poor thermal stability performance and great influence of temperature and pH value on lipase activity in the application of time-temperature indicator. The preparation process of lipase microcapsules was optimized by single factor test and orthogonal test with the concentration of sodium alginate, chitosan and calcium chloride as variables with the thermal stability, optimum temperature and pH value of lipase and lipase microcapsules were studied. The structure and morphology of lipase microcapsules was analyzed by infrared spectroscopy (FTIR) and scanning electron microscopy (SEM), and then the application of lipase microcapsule in time-temperature indicator was preliminarily studied. The optimal preparation conditions of lipase microcapsules were as follows: sodium alginate mass concentration was 30 g/L, chitosan mass concentration was 6 g/L, calcium chloride concentration was 0.3 mol/L, and the thermal stability of lipase microcapsules was significantly improved compared with the original lipase. The preparation technology of lipase microcapsule is stable and reliable, which has practical value in time-temperature indicator.