短期低温贮藏对南果梨果实货架期后熟衰老及品质的影响

Effects of short-term low-temperature storage on ripening and senescence and quality of‘Nanguo’pear fruit during shelf life

为研究短期低温贮藏对南果梨货架期后熟衰老及品质的影响,以南果梨果实为试验对象,低温(4℃)贮藏60 d后恢复常温[(23±2)℃]货架期,测定其成熟衰老及品质相关生理指标变化。结果表明,与未经低温处理常温自然后熟的对照相比,短期低温贮藏后转入货架期的南果梨果实乙烯高峰和呼吸高峰出现时间分别提前6,3 d。第15 d时,超氧阴离子产生速率和丙二醛积累分别提高1.26,1.33倍,总酚含量降低91.6%;同时软化速度加快,DPPH·清除率降低,VC含量、TA含量、类黄酮含量下降加快,PPO活性升高。短期低温贮藏的南果梨果实转入货架期后品质降低,后熟衰老进程加快,货架期缩短3 d,与乙烯含量增加和抗氧化能力减弱有关。研究为南果梨果实的贮藏保鲜提供参考。

In order to study effects of short-term low-temperature storage on ripening,senescence and quality of‘Nanguo’pear during shelf life,‘Nanguo’pears were used as the test material,after 60 days of storage at low temperature(4℃),pears were allowed to ripen at room temperature[(23±2)℃]to measure the changes of physiological indexes related to ripening,senescence and quality during shelf life.The results show that compared with controls which were naturally ripened at room temperature without low-temperature treatment,ethylene production and respiration peaks respectively appeared 6 d and 3 d earlier.At 15 d,O2-·production and MDA accumulation respectively increased by 1.26 times and 1.33 times,and the total phenol content decreased by 91.6%.Rates of softening were quickened,while DPPH·scavenging rate was reduced in Nanguo pear fruit during shelf life after short-term low-temperature storage.The ascorbic acid content,titratable acid content,total phenol content and flavonoids content declined faster,and the PPO activity was promoted than controls during shelf life.The shelf-life quality of Nanguo pears decreased,the ripening and senescence process was accelerated,and the shelf life was shortened by 3 d after short-term low-temperature storage,which might be related to the increase of ethylene production and the weakening of antioxidant capacity.This study provides reference for the storage and preservation of‘Nanguo’pear fruit.