褪黑素和短波紫外联合处理对鲜切麻竹笋挥发性化合物的影响

Effects of combined treatment of melatonin and ultraviolet C on volatile compounds of fresh-cut Ma bamboo shoots

中文关键词:  麻竹笋，挥发性香气化合物，气相色谱离子迁移谱，紫外照射，褪黑素

英文关键词:Ma bamboo shoots  volatile aroma compounds  gas chromatography-ion migration spectrometry  ultraviolet C  melatonin

中文摘要:

      目的 探究褪黑素和短波紫外(ultraviolet C, UV-C)保鲜处理方式对鲜切麻竹笋挥发性化合物的影响。方法 利用气相色谱-离子迁移谱法(gas chromatography-ion migration spectrometry, GC-IMS)结合偏最小二乘判别分析法对褪黑素处理、UV-C处理和鲜切麻竹笋样品的挥发性化合物进行分析。结果 GC-IMS检测结果表明麻竹笋挥发性成分以醇、醛和酯为主。鲜切麻竹笋中鉴定出60种挥发性化合物, 包括18种醇、10种酯、9种醛、9种烯烃、4种酮、3种酸和7种其他挥发性化合物。UV-C和褪黑素处理显著抑制鲜切笋发酵过程并且改变挥发性酯的种类和含量, 导致2-甲基丁酸乙酯、乙酸乙酯、乙酸甲酯、丁酸丙酯明显积累。与单独UV-C或褪黑素处理不同, 联合处理可以提高反式-2-丁烯酸乙酯、2-辛醇、3-甲基-1-戊醇、丙酸含量, 并抑制发酵过程中不良风味如对甲酚的积累。3-甲基吲哚、安息香醛、对甲酚、反式-2-庚烯醛(二聚体)、己醇聚合物可以作为判别不同处理贮藏麻竹笋的主要特征性标志物。结论 本研究为鲜切麻竹笋物理保鲜提供了理论支撑，为褪黑素和UV-C联合处理在果蔬保鲜上的应用奠定了基础。

英文摘要:

      Objective To explore the effects of melatonin and ultraviolet C (UV-C) fresh-keeping methods on volatile compounds in fresh-cut Ma bamboo shoots. Methods The volatile compounds of melatonin and UV-C pretreated and fresh-cut Ma bamboo shoots were analyzed and evaluated by gas chromatography-ion migration spectrometry (GC-IMS) and partial least squares methods. Results The results of GC-IMS showed that alcohol, aldehydes and esters were the main volatile components of bamboo shoots. Sixty kinds of volatile compounds were identified in fresh-cut Ma bamboo shoots, including 18 kinds of alcohols, 10 kinds of esters, 9 kinds of aldehydes, 9 kinds of alkenes, 4 kinds of ketones, 3 kinds of acids and 7 kinds of other volatile compounds. UV-C irradiation and melatonin treatment significantly inhibited the fermentation process of fresh shoots and changed the types and content of volatile esters, resulting in significant accumulation of ethyl 2-methylbutyrate, ethyl acetate, methyl acetate, and propyl butyrate. Different from UV-C irradiation or melatonin treatment alone, combined melatonin treatment could increase the content of ethyl trans-2-butenoate, 2-octanol, 3-methyl-1-pentanol and propionic acid, and inhibit the accumulation of undesirable flavor such as p-cresol during fermentation. 3-methylindole, benzoaldehyde, p-cresol, trans-2-heptenal (dimer) and hexanol polymer could be used as the main characteristic markers to distinguish different treatments of stored Ma bamboo shoots. Conclusion This study provides a theoretical support for the physical preservation of fresh-cut Ma bamboo shoots, and lays a foundation for the application of melatonin combined with UV-C in the preservation of fruits and vegetables.