采收成熟度对‘金奉’猕猴桃果实后熟品质的影响

Effects of harvest maturity on post-ripening quality of ‘Jinfeng’ kiwifruit

中文关键词:  ‘金奉’猕猴桃  采收成熟度  后熟品质

英文关键词:Jinfeng’ kiwifruit  harvest maturity  post-ripening quality

中文摘要:

      目的 探讨采收成熟度对‘金奉’猕猴桃果实后熟品质的影响。方法 以采收成熟度Ⅰ、Ⅱ、Ⅲ和Ⅳ(盛花后150、155、160和165 d)时期的‘金奉’猕猴桃果实为实验材料, 在(20±1) ℃条件下贮藏至果实完全软化, 通过测定贮藏期间果实失重率、腐烂率、呼吸强度等贮藏特性指标, 以及可溶性固形物、可滴定酸、淀粉、可溶性糖等营养品质指标, 利用主成分分析法综合评价采收成熟度对‘金奉’猕猴桃果实贮藏特性的影响。结果 贮藏期间, 猕猴桃果实在4个采收期的腐烂率、失重率、果糖、葡萄糖含量和固酸比值逐渐上升; 硬度、可滴定酸和可溶性淀粉含量逐渐下降; 呼吸强度、乙烯释放率、干物质、维生素C、可溶性糖、可溶性固形物和蔗糖含量呈先上升后下降趋势。采收期Ⅳ的果实腐烂率在贮藏6~10 d时显著低于其他3个采收期, 采收期Ⅲ的果实失重率在贮藏2~10 d时显著高于其他3个时期。采收期Ⅱ和Ⅲ的呼吸强度在贮藏6 d时出现峰值, 乙烯释放率分别在贮藏6 d和4 d时达到峰值, 且显著高于Ⅰ和Ⅳ。采收期Ⅲ的果肉和中柱的硬度和可溶性淀粉含量在贮藏4 d时显著低于其他3个采收期。采收期Ⅲ的果肉和中柱的可溶性固形物含量在贮藏0~4 d时显著高于其他3个时期, 果肉的可滴定酸含量除贮藏第2 d外均显著低于采收期Ⅰ和Ⅳ; 果肉的固酸比值在贮藏0~4 d时显著高于Ⅰ和Ⅳ。采收期Ⅱ、Ⅲ和Ⅳ果肉和中柱的可溶性糖、果糖、葡萄糖和蔗糖含量在贮藏0~4 d时显著高于采收期Ⅰ。主成分分析结果表明, 采收期Ⅲ综合得分在贮藏6 d时达到峰值2.56, 高于采收期Ⅰ (1.72)、Ⅱ (2.45)和Ⅳ (2.35)。结论 采收期Ⅲ(盛花后160 d)的‘金奉’猕猴桃果实贮藏品质最佳, 为最适采收成熟度。

英文摘要:

      Objective To explore the effects of harvest maturity on the post-ripening quality of ‘Jinfeng’ kiwifruit. Methods The ‘Jinfeng’ kiwifruits at harvest maturity Ⅰ, Ⅱ, Ⅲ and Ⅳ (150, 155, 160 and 165 days after full bloom) were used as test materials and stored at (20±1) ℃ until the fruits were completely softened. The effects of harvest maturity on the storage characteristics of ‘Jinfeng’ kiwifruit were comprehensively evaluated by measuring the storage characteristics such as weight loss rate, decay rate and respiratory intensity, and the nutritional quality indexes such as total soluble solids, titratable acid, starch and soluble sugar, and combining with principal component analysis. Results During storage, the decay rate, weight loss rate, fructose, glucose content and total soluble solids/titratable acid ratio of kiwifruit increased gradually during 4 harvest periods. Firmness, titratable acid content and soluble starch content decreased gradually. Respiratory intensity, ethylene release rate, dry matter, vitamin C, soluble sugar, total soluble solids and sucrose content increased first and then decreased. The decay rate of harvest period Ⅳ was significantly lower than that of other 3 harvest periods at storage 6–10 d, and the weight loss rate of harvest period Ⅲ was significantly higher than that of other 3 periods during storage 2–10 d. The respiratory intensity of Ⅱ and Ⅲ reached the peak at 6 d of storage, and the ethylene release rate reached the peak at 6 d and 4 d of storage, respectively, and was significantly higher than that of Ⅰ and Ⅳ. The firmness and soluble starch content of pulp and core in harvest period Ⅲ were significantly lower than those in other 3 harvest periods at 4 days of storage. The total soluble solids content in pulp and core of harvest period Ⅲ was significantly higher than that of other 3 periods at 0–4 d of storage, and the content of titratable acid in pulp was significantly lower than that of harvest period Ⅰ and Ⅳ except for the second day of storage, and the total soluble solids/titratable acid ratio of pulp was significantly higher than that of harvest periods Ⅰ and Ⅳ during 0–4 d of storage. The content of soluble sugar, fructose, glucose and sucrose in pulp and core of harvest period Ⅱ, Ⅲ and Ⅳ were significantly higher than those of harvest period Ⅰ during 0–4 d of storage. The principal component analysis results showed that the comprehensive score of harvest period Ⅲ reached a peak of 2.56 at 6 days of storage, which was higher than that of harvest period Ⅰ (1.72), Ⅱ (2.45) and Ⅳ (2.35). Conclusion The storage quality of ‘Jinfeng’ kiwifruit in harvest period Ⅲ (160 days after full bloom) is the best, which is the most suitable harvest maturity.