Yu Ai-Nong, Yang Yi-Ni, Yang Yan, Liang Miao, Zheng Fu-Ping, Sun Bao-Guo
Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University (BTBU), Beijing 100048, China.
School of Chemistry & Environmental Engineering, Hubei University for Nationalities, Enshi 445000 China.
Foods. 2020 Apr 13;9(4):488. doi: 10.3390/foods9040488.
Free and bound aroma volatiles from turnjujube during low temperature storage were extracted by headspace solid-phase microextraction. They were then characterized and identified using gas chromatography-mass spectrometry. Turnjujube was harvested and stored for 7, 14, and 21 days at 7 °C, the common temperature of display refrigerators in grocery stores. The results showed that 41 free and 24 bound aroma compounds were detected for the first time in turnjujube in both freshly harvested and stored turnjujube. The free and bound aroma compounds of turnjujube were markedly influenced by the storage time. The major free aroma compounds in turnjujube included esters, alcohols, aliphatic aldehydes, and aliphatic ketones. The major bound aroma compounds included borneol, eugenol, and isoeugenol, which contributed to sweet, floral, and herbaceous aroma after their hydrolysis. Freshly harvested turnjujube mostly had a fruity and herbaceous aroma, which diminished after storage at 7 °C. In contrast, the fatty aroma enhanced gradually over storage, and the floral aroma enhanced noticeably after storage for seven days. Foul odor was not detected even after storage at 7 °C for 21 days. The formation mechanisms of some aroma compounds were proposed.
采用顶空固相微萃取法提取低温贮藏期间冬枣中的游离态和结合态香气挥发物，然后利用气相色谱 - 质谱联用仪对其进行表征和鉴定。冬枣采收后于7℃（杂货店陈列冰箱的常见温度）贮藏7天、14天和21天。结果表明，在新鲜采收和贮藏后的冬枣中首次检测到41种游离态和24种结合态香气化合物。冬枣的游离态和结合态香气化合物受贮藏时间的影响显著。冬枣中的主要游离香气化合物包括酯类、醇类、脂肪醛和脂肪酮。主要的结合香气化合物包括冰片、丁香酚和异丁香酚，它们在水解后产生甜香、花香和草本香气。新鲜采收的冬枣大多具有果香和草本香气，在7℃贮藏后这种香气减弱。相反，脂肪香气在贮藏过程中逐渐增强，贮藏7天后花香香气明显增强。即使在7℃贮藏21天后也未检测到异味。文中还提出了一些香气化合物的形成机制。
