留树保鲜对‘纽荷尔’脐橙果实糖酸及色泽的影响

为研究留树保鲜与低温冷藏对‘纽荷尔’脐橙果实糖酸及色泽的影响,以‘纽荷尔’脐橙为试验材料,对留树保鲜和低温冷藏过程中果实色差指数、可溶性固形物、可溶性糖及有机酸含量变化进行测定。在2种贮藏方式下,‘纽荷尔’脐橙果实色差指数和总糖含量呈上升趋势,可滴定酸含量在整个贮藏过程中不断下降,而可溶性固形物含量变化不大;留树保鲜的果实糖酸比在贮藏40 d前低于低温贮藏,但在40 d后留树保鲜的糖酸比值迅速增加并超过冷藏果实的糖酸比;‘纽荷尔’脐橙果实蔗糖含量最高,其次是果糖和葡萄糖,且果实蔗糖、葡萄糖和果糖含量变化趋势表现一致,均随贮藏时间变化呈上升趋势;果实柠檬酸含量呈现下降趋势,酒石酸含量比较稳定,奎尼酸和苹果酸含量呈先下降后上升再下降的趋势。与低温冷藏相比,留树保鲜能显著提高‘纽荷尔’脐橙果实色差指数,延缓果实有机酸含量的下降,但可溶性固形物和可溶性糖含量无显著性差异,说明留树保鲜能提高‘纽荷尔’脐橙果实的贮藏品质。

Effects of On-tree Storage on Sugars,Organic Acids Contents and Color of ‘Newhall’ Navel Orange Fruit

To study the effects of on?tree storage and cold storage on sugars,organic acid contents and col?or of ‘Newhall’ navel orange fruit.In this study,‘Newhall’ navel orange fruits were stored on?tree and cold room,then the change of citrus color index ( CCI) ,total soluble solids ( TSS) ,sugars and organic acid contents were measured during storage.The results showed that CCI and total sugar contents increased while titratable a?cidity decreased and TSS was stable in‘Newhall’ navel orange fruits under the two storage methods.Compared with the cold storage,the sugar?acid radio of on?tree storage fruits was lower before 40 d,but increased rapidly and exceeded refrigerated fruits after 40 d of storage.In ‘Newhall’ navel orange fruit,sucrose content was the highest,followed by fructose content and glucose content, and their change trends were similar which all in?creased with storage time.Citric acid content showed a downward trend,and the change of tartaric acid content was not significant, quinic and malic acid contents decreased at first then rose and declined again in ‘Ne?whall’ navel orange fruits during the whole storage.Compared to cold storage,on?tree storage could significantly enhanced CCI and slowed the decrease of organic acid contents,but there was no significant deference in TSS and soluble sugars in ‘Newhall’ navel orange fruits,which indicated that on?tree storage could improved the storage quality of ‘Newhall’ navel orange fruits.