采收成熟度对冷藏水蜜桃果实品质和冷害的影响

 【目的】研究不同采收成熟度对南方软质型水蜜桃在低温下的贮藏效果及抗冷性，以探索适宜的果实采收成熟度，为软质型水蜜桃低温贮藏提供依据。【方法】以7-8成熟和9成熟2种不同采收成熟度的“湖景蜜露”水蜜桃为材料，测定在1℃28 d贮藏期间果实腐烂指数、硬度、可溶性固形物、可滴定酸、VC含量、呼吸强度、乙烯释放速率、相对电导率、褐变指数和SOD、POD等品质及生理生化指标。【结果】7-8成熟的水蜜桃在冷藏过程中果实硬度增加，出汁率在7 d后开始下降，不能正常后熟，出现明显的冷害症状，果实的品质降低;而9成熟的水蜜桃在冷藏期间果实硬度缓慢下降，出汁率平稳增加，能正常后熟，未出现明显的冷害症状，保持了较高的商品价值。与7-8成熟的水蜜桃果实相比，9成熟的水蜜桃在冷藏期间褐变指数较小，可溶性固形物和VC含量较高，乙烯释放量和呼吸强度较大，SOD和POD活性较高。【结论】9成熟的水蜜桃具有较好的抗冷性，适宜于低温贮藏。

Effects of Harvest Maturity on Quality and Chilling Injury of Juicy Peaches During Low Temperature Storage

【Objective】 This research investigated the effects of different harvested maturities on quality attributes and chilling injury of peach fruit (Prunus persica L. Batsch cv. Hujingmilu) in low temperature storage, and further explore the optimal harvested maturity, which is useful for guiding storage technique of soft peaches in south China. 【Method】 Changes in rotten rate, flesh firmness, total soluble solids (TSS), titratable acidity (TA) and ascorbic acid, respiration rate, relative leakage rate, browning index, superoxide dismutase (SOD) and peroxidase (POD) of ‘Hujingmilu’ peaches were investigated at 1℃ for 28 days. 【Result】 As compared to the fruits with 7-8 maturity-degree at 1℃, the fruits with 9 maturity-degree showed a stronger tolerance to cold stress, and kept better quality during low temperature storage periods. In addition, the fruits with 9 maturity-degree showed an increase in activities of SOD and POD, reducing accumulation of free radical and alleviating chilling injury. 【Conclusion】 Thus, 9 maturity-degree should be suggested as the best harvest maturity of juicy peaches in low temperature storage.