气调包装对带叶荔枝褐变及品质的影响

Effect of High Oxygen Atmospheric Packaging on the Browning and Quality of Litchi Fruits with Leaves

摘要:

本文研究了在高氧（100% O2）气调包装条件下，带叶荔枝的营养品质以及褐变相关酶活性的变化规律。结果表明：与对照组(空气包装)相比，高氧气调包装抑制了荔枝的呼吸强度，相对应其呼吸过程产生的二氧化碳（CO2）量下降，降低了带叶荔枝贮藏前期和后期的褐变程度，显著抑制了过氧化物酶（POD）的活性，显著推迟了多酚氧化酶（PPO）活性高峰的出现，说明了带叶荔枝的褐变与POD、PPO两种酶有一定的相关性；在贮藏的前6 d，可溶性蛋白、花色素苷和总多酚的含量都比对照低，但在贮藏期的第9和12 d后，其含量比对照组要高；另外，高氧气调包装不利于荔枝汁维生素C（Vc）的含量的维持，而对可溶性固形物和可滴定酸的影响不明显。因此，高氧气调包装能够延缓带叶荔枝的褐变，但是不利于其果汁Vc含量的维持。

Abstract:

The changes of nutritional quality and activities of browning-related enzymes were studied in the litchi fruits with leaves under high oxygen atmospheric packaging. Compared with the control (air packaging), high oxygen atmospheric packaging inhibited respiratory intensity of litchi fruit，with decreasing of formation of carbon dioxide (CO2). The treatment reduced the degree of browning after storage. Peroxidase (POD) activity in the pericarp of litchi fruit was significantly lower than control, while the maximal activity of polyphenol oxidase (PPO) was markedly delayed. It was illustrated that the browning of the litchi fruits with leaves had certain correlation with POD and PPO. The variation trends of soluble protein, anthocyanin and total polyphenol contents were similar: the contents of them were lower than control during the first 6 days of storage. But at day 9 and day 12, the contents were higher than control. Vitamin C (Vc) in litchi juice decreased significantly under high oxygen packaging, while soluble solids and titratable acid showed little changes. Therefore, high oxygen atmospheric packaging was benefit to the delay of browning, but not benefit with the maintenance of Vc.