为研究LED蓝色光照对于不同品种气调包装荔枝采后品质的影响，以三个品种带枝叶的荔枝（桂味、糯米糍和妃子笑）为实验材料，采用气调包装贮藏于4 ℃冷库中，以每天12 h照射LED单色蓝光[主波长(449±5) nm，光强(110±5) lx]的包装荔枝为处理组，并以避光贮藏包装荔枝作为对照组，在第0、2、4、6、8天分别取样，然后测定相关品质指标。结果表明，LED单色蓝光光照处理均能缓解不同品种荔枝的采后褐变程度，经蓝光照射处理的妃子笑荔枝6 d的褐变系数仅为0.23，桂味荔枝8 d的褐变系数仅为0.37。LED蓝光处理均能够抑制不同品种荔枝中丙二醛（MDA）含量的积累，延缓总酚、可溶性固形物（TSS）以及花青素（LPCs）含量的减少，降低可滴定酸（TA）的含量并有效抑制了果皮多酚氧化酶（PPO）、过氧化物酶（POD）活性的增加。因此，LED单色蓝光处理能有效抑制不同品种气调包装荔枝采后保鲜品质的下降，为荔枝采后绿色保鲜技术研发提供一定的理论依据。

The effect of LED blue light treatment combined with modified atmosphere packaging on the quality of different varieties of litchi after harvesting was investigated. Three litchi varieties with leaves (Guiwei, Nuomici and Fei Zi Xiao) were selected for the investigation. They were stored at 4 ℃ in modified atmosphere packaging. The packaged litchi fruits were irradiated using monochromatic blue LED light (primary wavelength (449±5) nm, light intensity (110±5) lx) for 12 h per day (treatment group), whereas the control group was stored in dark. Litchi samples were collected on days 0, 2, 4, 6 and 8, and then the relevant quality indices were measured. The results show that monochromatic blue LED light treatment could alleviate the degree of postharvest browning of the different litchi varieties. The browning coefficient on the sixth day of irradiated Fei Zi Xiao litchi was only 0.23, and that of Guiwei litchi on the eighth day was only 0.37. LED blue light treatment also inhibited the accumulation of malondialdehyde (MDA) in different varieties of litchi, and delayed the reduction of total phenols, total soluble solids (TSS), anthocyanins (LPCs), and titratable acid (TA) content. Moreover, the polyphenol oxidase (PPO) and peroxidase (POD) activities were effectively inhibited. Thus, the combination of LED blue light treatment combined and modified atmosphere packaging demonstrates remarkable efficacy in preventing the deterioration of postharvest quality of different litchi varieties, thereby providing the theoretical basis for the research and development of postharvest preservation technology specific to litchi.

广东省重点研发计划项目（2020B0202080003）；茂名市科技计划项目（2021S0062）