不同成熟度软枣猕猴桃果实的划分标准及贮藏特性

【目的】确定软枣猕猴桃果实成熟度的划分标准,进而确定不同销售需求的最佳采收期,并对在冷库贮藏的七成熟、八成熟和九成熟的果实特性进行研究,为不同成熟度的软枣猕猴桃贮藏特性研究提供理论依据。【方法】测定软枣猕猴桃不同采收期果实的硬度、可溶性固形物、可滴定酸、淀粉、单宁、种子转色指数,采用相关性分析法和层次分析法对数据进行处理分析,确定各分级指标权重,建立软枣猕猴桃综合值评分模型;并以此为标准,对果实成熟度进行分级,测定不同采收期的软枣猕猴桃冷藏期间的理化指标。【结果】盛花期后76 d和78 d果实的6个指标综合评分≤0.3209,划分为七成熟,盛花期后80 d和82 d果实的6个指标综合评分为0.3209—0.4562,划分为八成熟,盛花期后84、86、88、90和92 d果实的6个指标综合评分为0.4562—0.6440,划分为九成熟,盛花期后94和96 d果实的6个指标综合评分≥0.6440,划分为十成熟。在贮藏过程中,八成熟果实在后期腐烂指数显著低于七成熟的果实,硬度显著高于七成熟的果实,八成熟和九成熟果实的单宁含量在贮藏14 d后一直处于较低状态,八成熟果实的V_C含量在贮藏70 d时最高,七成熟果实可溶性固形物含量显著低于其他成熟度的果实,八成熟和九成熟果实的可滴定酸含量增减程度差异不大。七成熟果实不能在采后的贮藏过程中完成后熟,达不到预期的口感与风味;九成熟果实在贮藏后期风味良好,但贮藏期最短;八成熟果实贮藏后各项生化指标可达到最佳状态。【结论】软枣猕猴桃果实的6个指标综合评分分别为≥0.6440、0.4562—0.6440、0.3209—0.4562、≤0.3209时,可将果实成熟度确定为十成熟、九成熟、八成熟和七成熟;七成熟果实口感与风味不好,八成熟果实适合长期贮藏、错季节上市及远距离运输后销售,九成熟果实适合采后本地销售鲜食及加工。

Classification Criteria and Storage Characteristics of Actinidia Arguta Fruits with Different Maturities

【Objective】The aim of this study was to establish the classification criteria of different maturities to determine the optimal harvest time of Actinidia arguta fruits. Furthermore, the fruit qualities of 70%, 80% and 90% maturity levels were investigated, in order to provide theoretical guidance for the storage characteristic studies of Actinidia arguta fruits.【Method】Different indicators, including hardness, seed color transformation index, the contents of soluble solids, titratable acid, starchand tannin, were studied and analyzed by correlational and hierarchy analysis. Consequently, the comprehensive scoring model was established for the classification criteria with different fruit maturities. Then the physico-chemical changes of fruits at different harvesting stages were determined.【Result】During blossom period, the comprehensive scores of fruits were ≤0.3209 (at 76 and 78 d), 0.3209-0.4562 (at 80 and 82 d), 0.4562-0.6440 (at 84 and 92 d), ≥0.6440 (at 94 and 96 d), the maturity levels were 70%, 80%, 90% and 100%, respectively. Compared with 70% maturity fruits, the decay index of the 80% maturity fruits was significantly lower and the hardness was significantly higher. The contents of tannin and soluble solids of 80% and 90% maturity fruits were similar, and the other indicators could reach optimum ripeness during storage, but the latter had shorter storage life. The70% maturity fruits, which soluble solid content was the lowest, which couldn’t undergo after-ripening process during storage.【Conclusion】The comprehensive scores of Actinidia arguta fruit were ≥0.6440, 0.4562-0.6440, 0.3209-0.4562, ≤0.3209, and the corresponding maturities were 100%, 90%, 80% and 70%, respectively. Fruits of 80% maturity level were more suitable for long-term storage, staggered season and long-distance selling. Fruits of 90% maturity level were preferred to sale and process locally.