中文摘要：

为了延缓鲜切山药的褐变和品质劣变,延长保鲜期。从洋葱中提取洋葱油,结合保鲜剂柠檬酸和壳聚糖,以色差L＊值和感官评分为考察指标,在单因素试验的基础上进行正交试验,筛选适合鲜切山药保鲜的复合保鲜剂配方。结果表明：鲜切山药最佳保鲜剂组合为0.6%洋葱油＋1.0%柠檬酸＋1.0%壳聚糖,与清水处理相比,该组合可显著抑制鲜切山药贮藏过程中多酚氧化酶（PPO）和过氧化物酶（POD）的活性,降低鲜切山药的相对电导率和丙二醛（MDA）含量,延缓失重和软化,保持鲜切山药的亮度和总酚含量,维持鲜切山药可溶性固形物和还原糖含量,且具有较好的感官品质。与对照组相比,该复合保鲜剂可使鲜切山药保鲜期延长6d左右。

英文摘要：

In order to com rol the browning and quality deterioration of fresh-cut yam and extend its shelf life, By using the onion uil ex- tracted from on/on, which was combined with citric acid and chitosan, taking die L values and sensory score as index, the for mula of compound prescrvative for fresh cut yam was optimized by single factor and orthogonal experiments. The results showed that the optimal formula of preservative for fresh-cut yam was 0. 6% onion oil ＋ 1.0% citric acid ＋ 1.0% chhosan. This formula could significantly inhibit the activities of polyphenol oxidase（PPO） and peroxidase（POD）, reduce relative conductivity and the accumulation of MDA content, delay weight loss and softening, keep brightness and total phennl content, maintain the content of total soluble solid, soluble sugar and reducing sugar, and has better sensory quality. This formula extended the shelf life of fresh cut yam about 6 d corn pared with the control group.