本研究以冬枣果实为试验材料，用20 μL/L一氧化氮（NO）气体熏蒸冬枣果实3 h，置于0 ℃、相对湿度为90%~95%的冷库贮藏75 d，定期测定冬枣果实挥发性物质、乙醇代谢产物及关键酶活性的变化。结果表明，贮藏期冬枣果实共鉴定出47种挥发性物质，主要包括醇类、醛类、酯类、酸类、酮类。在采收当天、以及对照组和NO熏蒸处理组贮藏45 d和75 d后，分别检测出24、37、38、45和46种挥发性成分。贮藏期间果实醛类物质的变化多以先上升后下降为主，醇类和酯类物质的种类和含量大致主要呈增加趋势，NO对于醛类物质的作用因贮藏时间和醛类种类有所不同，而NO能有效抑制醇类和酯类含量增加。同时，NO处理显著抑制了丙酮酸脱羧酶（PDC）和乙醇脱氢酶（ADH）的活性，进而抑制了果实贮藏期间乙醇和乙醛含量的积累。说明NO处理能较好地保持冷藏果实挥发性物质的含量，延缓异味产生。

In this study, winter jujube fruits were used as experimental materials. Winter jujube fruits were subjected to a 3 h fumigation with 20 μL/L of nitric oxide (NO) and stored at 0 oC and 90%~95% of relative humidity for 75 d. Changes in volatile compounds, ethanol metabolites and activities of key enzymes of the winter jujube fruits were measured regularly during the storage. The results showed that a total of 47 volatile compounds were identified in the winter jujube fruits, mainly including alcohols, aldehydes, esters, acids, and ketones. After 45 and 75 days of the storage, 24, 37, 38, 45 and 46 volatile components were detected in the control and NO fumigated groups, respectively. During cold storage, the aldehydes in fruit mostly increased first and then decreased, while the types and contents of alcohols and esters generally increased. The effects of NO fumigation on aldehydes varied depending on the storage time and the type of aldehyde, whilst NO could effectively inhibit the increases in the contents of alcohols and esters. Meanwhile, NO fumigation significantly inhibited the activities of pyruvate decarboxylase (PDC) and alcohol dehydrogenase (ADH), thereby suppressing the accumulation of ethanol and acetaldehyde in the winter jujube fruit during storage. These results suggested that NO treatment could preserve the contents of volatile substances and delay the generation of off-flavor in the winter jujube fruit during cold storage.

国家重点研发计划项目(2018YFD0401305-5)；天津市科技计划项目（17PTWYHZ0030；18ZYPTJC00020）