目的 研究纳米复合材料涂膜对甘薯的保鲜作用，以改善甘薯的贮藏品质。方法 以壳聚糖/蒙脱石/乳清分离蛋白为原料制备可食性纳米复合保鲜材料，通过涂膜保鲜手段研究对“心香”型甘薯的保鲜贮藏效果，并正交优化涂膜配比。结果 在温度为(25±2)℃，相对湿度为(65±5)%的条件下，纳米复合涂膜保鲜材料能够减缓甘薯质量损失率、可溶性糖含量及菌落总数的上升，减少甘薯淀粉含量的损失，延缓甘薯代谢作用，较好地维持了甘薯品质，达到了较为显著的保鲜效果。正交试验得出了纳米复合材料涂膜剂的最适配比，即壳聚糖质量浓度为20 g/L，蒙脱石质量浓度为12 g/L，乳清分离蛋白质量浓度为60 g/L。结论 开发了一种新型甘薯涂膜剂，为其他纳米涂膜保鲜材料的研究提供了参考。

The work aims to study the preservation effect of nanocomposite coating on sweet potato in order to improve the storage quality of sweet potato. Chitosan/Montmorillonite/whey protein isolate was used as raw materials to prepare edible nanocomposite preservative. The fresh-keeping effect of coating preservation on 'Xinxiang' type sweet potato was studied, and the coating composition was optimized orthogonally. At the temperature of (25±2)℃ and the relative humidity of (65±5)%, the nanocomposite coating preservative can slow down the increase of weight loss rate, soluble sugar content and total number of colonies of sweet potato, reduce the starch content loss, delay the Metabolism and maintain the quality of sweet potato well, thus achieving a more significant fresh-keeping effect. The best fit ratio of nanocomposite coating agent was obtained by orthogonal experiment:the mass concentration of chitosan was 20 g/L, the mass concentration of montmorillonite was 12 g/L, and the mass concentration of whey protein isolate was 60 g/L. A new sweet potato coating film is developed, which provides a new reference for the study of other nano-coated preservatives.