Solvent-free glycerin modified tetraethoxysilane (TEOS) sol-gel was prepared to obtain enzyme immobilization materials without toxic reagents and suitable for food industry. The material prepared has good food safety and high biocompatibility, and the optimum modification conditions is TEOS:glycerin molar ratio=1:0.25, solid acid catalyst 3 g.(50 mL)-1 TEOS, temperature 50℃ for 72 h. The hydrophilicity of the modified TEOS is significantly increased with water solubility of 0.58 g . mL-1. The lipase immobilized shows high catalytic activity and strong structural rigidity. L-ascorbyl palmitate synthesis catalyzed by immobilized and free enzymes is studied under same conditions, and the immobilized enzyme shows better performance.%为了获得适用于食品工业且固定化酶性能优异的固定化材料，规避在固定化材料制备过程中使用影响食品安全性的试剂，在无溶剂体系中以丙三醇改性四乙氧基硅烷(TEOS)获得改性硅烷凝胶。经过试验研究，获得的优化改性工艺条件为原料摩尔比四乙氧基硅烷(TEOS)：丙三醇=1：0.25，固体酸催化剂3 g.(50 mL)-1 TEOS，反应温度50℃，反应时间72 h。优化工艺获得的改性四乙氧基硅烷亲水性明显增强，在水中的溶解量可达0.58 g.mL-1。使用改性四乙氧基硅烷固定化假丝酵母脂肪酶，酶的催化活性得到良好保留，酶分子的结构刚性得到增强，和游离酶在相同条件下催化L-抗坏血酸棕榈酸酯的合成，改性硅烷凝胶固定化酶表现出比游离酶更好的催化活性。经改性后的硅烷凝胶是食品安全性良好的酶固定化材料。
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