modified atmosphere packaging delays enzymatic browning and maintains
quality of harvested litchi fruit during low temperature storage
sajid alia,b, ahmad sattar khana,⁎, aman ullah malika, muhammad akbar anjumb,
aamir nawazb, hafiz muhammad shoaib shaha
a postharvest research and training centre, institute of horticultural sciences, university of agriculture faisalabad, 38040, pakistan
b department of horticulture, faculty of agricultural sciences and technology, bahauddin zakariya university multan, 60800, pakistan
abstract
postharvest skin browning of litchi is the major issue which substantially affects its visual quality and market potential. effect of modified atmosphere packaging (map) was studied to manage its surface browning and various quality attributes during storage at 5 ± 1 °c. it was noted that fruits kept under map exhibited reduced decay, browning index and loss of fresh weight. map storage of fruits markedly suppressed polyphenol oxidase (ppo) activity and delayed production of superoxide anion (o2–%), malondialdehyde (mda), hydrogen peroxide (h2o2) and relative electrolyte leakage with higher anthocyanin concentrations. likewise, map stored fruits had
higher total soluble solids (tss), ascorbic acid content and titratable acidity (ta) with lower peroxidase (pod) activity. in addition, sensory quality, total phenolic content (tpc), radical scavenging activity, superoxide dismutase (sod), catalase (cat) and ascorbate peroxidase (apx) activities were also markedly higher in map kept
fruits. so, litchi fruits storage under map packaging was suitable to delay its postharvest browning and to conserve biochemical attributes and antioxidative enzymes during 28 days cold storage.
荔枝采后果皮褐变是影响荔枝视觉品质和市场潜力的主要问题。研究了气调包装（map）在5±1℃贮藏过程中对果实表面褐变和各种品质指标的影响，结果表明，map贮藏的果实腐烂程度降低，褐变指数降低，鲜重下降。随着花色素苷浓度的增加，果实贮藏显著抑制了多酚氧化酶（ppo）活性和超氧阴离子（o2-）、丙二醛（mda）、过氧化氢（h2o2）的产生及电解质的相对渗漏。同样，地图上储存的水果总可溶性固形物（tss）、抗坏血酸含量和可滴定酸度（ta）较高，过氧化物酶（pod）活性较低。此外，map的感官品质、总酚含量、自由基清除活性、超氧化物歧化酶（sod）、过氧化氢酶（cat）和抗坏血酸过氧化物酶（apx）活性也明显高于对照组水果。因此，采用map包装贮藏荔枝果实，可延缓果实采后褐变，并可在28天冷藏期间保存生化特性和抗氧化酶。
keywords:antioxidant activity、enzymatic browning、litchi chinensis、oxidative stress、sensory quality
关键词：抗氧化活性、酶促褐变、荔枝、氧化应激、感官品质