高 O2薄膜气调包装对鲜切莲藕保鲜效果的影响

为了研究高O2气调包装对鲜切莲藕保鲜效果的影响，本试验以鲜切莲藕为材料，分别向装有鲜切莲藕的薄膜中充入初始体积分数为100% O2、90% O2＋10% CO2、80% O2＋20% CO2、70% O2＋30% CO2的气体，以自然大气为对照（CK），对4 ℃贮藏期间鲜切莲藕的贮藏特性进行了测定。结果表明，适宜浓度的高O2使鲜切莲藕乙烯释放量降低了65.14%、呼吸强度降低了43.57%，维生素C的损失减少了26.43%，多酚氧化酶（PPO）活性降低了68.67%，褐变度降低了17.65%；同时，适宜浓度的高O2还可降低可溶性糖和淀粉含量，减少干、鲜重的损失，维持较高的超氧化物歧化酶（SOD）活性，延缓丙二醛（MDA）的积累，有效维持鲜切莲藕的贮藏品质。其中，保鲜效果以90% O2＋10% CO2处理最好，然后依次为100% O2、80% O2＋20% CO2和70% O2＋30% CO2，CK效果最差。该试验结果表明，采用适宜浓度的高O2气体进行气调包装保鲜，能有效保持鲜切莲藕的贮藏品质。

Effects of Modified Atmospheres Package with High O2 on Storage Properties of Fresh-cut Lotus Root

In order to study the role of modified atmospheres package （MAP） with different proportion of high O2 in controlling storage attributes, fresh-cut lotus root stored in modified atmospheres packages were analyzed with initial atmospheres of 100% O2, 90% O2＋10% CO2, 80% O2＋20% CO2, 70% O2＋30% CO2, and air as control check （CK） at 4 ℃. The results showed that the treatments with proper concentration of high O2 lowered the respiration rate by 43.57%, delayed ethylene release by 65.14%, suppressed the decrease of ascorbic acid by 26.43%, decreased the activity of polyphenol oxidase （POD） by 68.67% and reduced the degree of brown by 17.65%; meanwhile, it could also diminish soluble sugar and starch content, minimize the loss of dry and fresh weight, maintain a higher superoxide dismutase （SOD） activity, postpone the accumulation of malonaldehyde （MDA） and effectively retain the storage qualities of fresh-cut lotus root. Among the treatments, the maximum efficacy was observed with a MAP with initial atmosphere of 90% O2 ＋ 10% CO2, followed by 100% O2, 80% O2＋20% CO2 and 70% O2＋30% CO2, while CK had the poorest effect. The results suggested that an appropriate concentration of high O2 in MAP could maintain the quality of fresh-cut lotus root during storage.