短波紫外线结合发光二极管红光辐照对香椿保鲜效果的影响

Effects of combined short-wave ultraviolet C and light-emitting diode red light irradiation on preservation of Toona sinensis

中文关键词:  香椿  短波紫外线  发光二极管  辐照  保鲜

英文关键词:Toona sinensis  short-wave ultraviolet C  light-emitting diode  irradiation  preservation

中文摘要:

      目的 比较短波紫外线(ultraviolet C, UV-C)与发光二极管(light-emitting diode, LED)红光复合辐照和单一LED红光辐照对贮藏期香椿采后保鲜效果的影响。方法 将挑选后的香椿分为3组, 在4℃下贮藏, 通过测定感官指标、失重率、色差值、可溶性固形物含量、维生素C (vitamin C, VC)含量、还原糖含量、菌落总数、丙二醛(malondialdehyde, MDA)含量、1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl, DPPH)自由基清除能力、过氧化物酶(peroxidase, POD)和多酚氧化酶(polyphenol oxidase, PPO)活性指标比较不同处理的差异。结果 将红光复合辐照与单一LED红光辐照的处理效果比较后发现: 在外观品质方面, 前者显著地提高香椿的感官品质, 其感官品质评分比对照高9.6分; 有效地降低香椿的失重率, 其失重率仅为对照的52.5%; 在营养品质上, 前者可以保持更高的可溶性固形物、VC和还原糖含量, 其VC含量是对照的11.1倍; 前者不仅有效地抑制香椿叶片中微生物的生长, 还显著地减缓MDA含量的积累, 其MDA含量只有对照的72.3%; 前者还保持更高的DPPH自由基清除能力, 也显著地提高POD和PPO的活性, 其PPO活性比对照高32.4%。结论 UV-C结合LED红光辐照和单一LED红光辐照都有利于保持香椿的贮藏品质, UV-C结合LED红光复合辐照对香椿的保鲜效果更好。

英文摘要:

      Objective To compare the effects of short-wave ultraviolet C (UV-C) combined with light-emitting diode (LED) red light irradiation and single LED red light irradiation on postharvest preservation of Toona sinensis during storage. Methods The selected Toona sinensis was divided into 3 groups and stored at 4℃. The differences of different treatments were compared by measuring the sensory index, weight loss rate, color difference value, soluble solid content, vitamin C (VC) content, reducing sugar content, total bacterial count, malondialdehyde (MDA) content, free radical scavenging ability of 1,1-diphenyl-2-picrylhydrazyl (DPPH), peroxidase (POD) and polyphenol oxidase (PPO) activity indexes. Results After comparing treating results obtained from combined red light irradiation and single LED red light irradiation, it was found that: In terms of exterior quality, the former more significantly increased its sensory quality with 9.6 points higher score than the control, and it effectively reduced weight loss rate to only 52.5% of the control; and in terms of nutritional quality, the former maintained relatively higher content of soluble solids, VC and reducing sugar, of which its VC content was 11.1 fold of the control; the former not only more effectively suppressed microbial growth in Toona sinensis leaves, but also more significantly retarded accumulation of MDA, the content of which was only 72.3% of the control; the former also maintained higher DPPH free radical scavenging capacities, and also more significantly elevated POD and PPO activities, of which its PPO activity was 32.4% higher than that of control. Conclusion Both combined irradiation of UV-C and LED red light and single LED red light irradiation is beneficial to maintenance of storage qualities of Toona sinensis, preservation effects of combined UV-C and LED red light irradiation is preferable.