目的 研究添加无机纳米TiO2和无机纳米TiO2+Ag的聚乳酸膜对冷却肉保鲜效果的影响。方法 采用溶剂浇注法，以聚乳酸（PLA）为成膜基质，添加质量分数为9%的柠檬精油（LEO）作为增塑剂和纳米粒子，制备PLA膜、PLA/LEO膜、PLA/LEO/TiO2膜、PLA/LEO/TiO2+Ag膜，用来包装冷却肉，以LDPE膜包装作为对照组，在冷藏温度（4±1）℃下测定其理化指标的变化规律。结果 采用聚乳酸纳米抗菌复合膜保鲜冷却肉的效果均显著大于LDPE膜、PLA膜、PLA/LEO膜（P＜0.05）。聚乳酸纳米抗菌复合膜能够有效地抑制冷却肉表面微生物的生长繁殖，延缓蛋白质和脂肪的氧化，延长冷却肉货架期。结论 聚乳酸纳米抗菌复合膜可以保证冷却肉的品质，以及延长货架期，且PLA/LEO/TiO2+Ag膜包装冷却肉的保鲜效果最佳。

The aim of this work is to study preservative effects of different polylactic acid antibacterial nanocomposite film on chilled pork. The solvent casting method was used. 9% lemon essential oil as plasticizer and inorganic nanoparticles were added in polylacit acid to prepare PLA film, PLA/LEO film, PLA/LEO/TiO2 film and PLA/LEO/TiO2+Ag film to pack chilled pork. LDPE film packaging as the comparison, physical and chemical indexes of chilled pork packaged by those film under (4±1)℃ storage were analyzed. Results demonstrated thatthe preservative effect of polylactic acid antibacterial nanocomposite film is obviously higher than LDPE film, PLA film and PLA/LEO film(P＜0.05). Polylactic acid antibacterial nanocomposite film can inhibit bacterial growth on the surface of chilled pork, delay oxidation of protein and lipids and help to extend shelf-life of chilled pork. In a summary, polylactic acid antibacterial nanocomposite film can ensure the quality and extend shelf-life of chilled pork, among which PLA/LEO/TiO2+Ag had the best performance on chilled pork packaging.