EFF和硝酸钙混合液对薄皮甜瓜采后香气成分的影响

研究促进保鲜配方(EFF)和硝酸钙混合液对薄皮甜瓜采后香气成分的影响。以采后七成熟薄皮甜瓜‘玉美人’和‘日本甜宝’为试材，用EFF和硝酸钙混合液(EFF 2%和硝酸钙0.5%(V/V))浸泡，分别以浸泡清水和0.5%硝酸钙为对照(CK1和CK2)，在15℃恒温培养箱中贮藏21d，测定贮藏期间果实香气成分的变化。结果表明，经混合液浸泡后，延缓了果实质量、硬度、水分的降低速率及可溶性固形物的消耗。果实贮藏前期，香气物质中醇类和醛类为主要成分，随着果实逐渐成熟衰老，两者含量逐渐减少，而酯类含量逐渐增加，且以乙酸酯类为主，其次是草酸酯类和其他酯类。处理果实中己醛含量和其他4种醛的总量均显著高于两个对照(P＜0.05)，两个品种处理果实香气物质总含量均高于两个对照，而且香气物质出现高峰晚于两个对照，减少了香气成分的损失。两个品种比较，‘日本甜宝’更耐贮藏。综合分析得出，EFF和硝酸钙的混合液比单独使用硝酸钙更利于保持果实品质及香气成分，延缓采后果实的成熟与衰老。

Effect of Enhanced Freshness Formulation and Calcium Nitrate on Aroma Compounds in Postharvest Oriental Sweet Melons (Cucumis melo var. makuwa Makino) during Storage Period

Oriental sweet melons ‘Yumeiren’ and ‘Japanese Tianbao’ were immersed in the blended solution (2% EFF and 0.5% calcium nitrate) for 3 min before storage in incubators with temperature of 15 ℃ and a relative humidity of 85% for 21 days. Melons were immersed in plain water (CK1) or 0.5% calcium nitrate solution (CK2) as the controls. The change in relative physiological indexes and aroma compounds were measured during storage period. Compared with both controls, the blended solution treatment alleviated the decrease of fruit weight, firmness, water content and soluble solid content. Alcohols and aldehydes were the major compounds during the early stage of storage period, and then decreased gradually. Meanwhile, the contents of esters revealed an increasing trend. Among esters, acetic esters were the major compounds, which followed by oxalic acid esters and other esters. The concentrations of hexanal and other 4 aldehydes in melons with blended solution treatment were significantly higher (P ＜ 0.05) than those in two controls. In addition, the content of total aroma compounds in both cultivars was higher and the appearance of aroma peak was later than that in two controls. Compared with both cultivars, ‘Japanese Tianbao’ had a longer shelf-life. Taken together, these results indicate that the blended solution (2% EFF and 0.5% calcium nitrate) is more effective than calcium nitrate solution on maintaining fruit quality, decreasing the loss of aroma compounds and delaying the ripening and senescence of oriental sweet melons.