氯化钙处理对采后百香果果实品质及柠檬酸代谢的影响

Effects of Calcium Chloride Treatment on Quality and Citric Acid Metabolism of Postharvest Passion Fruit

百香果为呼吸跃变型果实,采后贮藏过程中易发生脱囊、皱缩等问题。为延长其采后贮藏保鲜期,提升贮藏品质,该研究以‘台农1号’为试材,采用2%、4%氯化钙溶液浸泡处理,不浸泡为对照,定期取样测定失重率、可食率、可溶性固形物、柠檬酸含量等相关指标,探索常温贮藏时适宜氯化钙处理浓度及柠檬酸积累调控机制。结果表明,百香果果实贮藏过程中失重率呈上升趋势,可食率呈下降趋势,可溶性固形物和柠檬酸含量呈先升后降的变化趋势。2%CaCl2处理能够使果实失重率降低12.70%,可食率、可溶性固形物和柠檬酸含量分别提高11.65%、6.61%和18.77%。柠檬酸合酶活性变化与柠檬酸含量变化趋势相似,且二者呈显著正相关(P<0.05)。综上所述,柠檬酸合酶主要调控柠檬酸的积累,且2%CaCl_(2)处理保鲜效果最好。该结果可为百香果采后有机酸积累及品质调控提供理论指导。

Passion fruit is a kind of respiratory climacteric fruit,which is prone to capsule removal and shrinkage during post-harvest storage.In order to prolong its post-harvest storage period and improve storage quality,‘Tainong No.1'passion fruit was used as the test material in this study,which was soaked with 2%and 4%calcium chloride respectively,with no soaking as the control.The relevant indexes such as weight loss rate,edibility rate,soluble solids,citric acid content,etc.,were measured regularly to explore the suitable concentration of calcium chloride and the regulation mechanism of citric acid accumulation during room temperature storage.The results showed that the weight loss rate of passion fruit increased during storage,the edible rate decreased,and the content of soluble solids and citric acid increased first and then decreased.2%CaCl_(2) treatment could significantly reduce fruit weight loss rate by 12.70%,increase fruit edible rate,soluble solids and citric acid content by 11.65%,6.61%,and 18.77%,respectively.The results of enzyme activity determination showed that the change trend of citric acid synthase activity was similar to that of citric acid content,and there was a significant positive correlation between them(P<0.05).In summary,citrate synthase mainly regulates the accumulation of citric acid,and 2%CaCl_(2) treatment has the best preservation effect.The results provided theoretical guidance for postharvest organic acid accumulation and quality control of passion fruit.