降温方法对晚采鸭梨果心PPO基因表达和褐变的影响  

Effect of different cooling methods on PPO gene expression and fruit browning of late-harvest Yali pear

作　　者：李月圆 樊晓岚 张引引 王海凤 韩艳文 闫师杰 王晓闻[1] LI Yue-yuan;FAN Xiao-lan;ZHANG Yin-yin;WANG Hai-feng;HAN Yan-wen;YAN Shi-jie;WANG Xiao-wen(College of Food Science and Engineering, Shanxi Agricultural University, Taigu 030801;College of Horticulture and Landscape, Tianjin Agricultural University, Tianjin 300384;Center for Agricultural Analysis and Measurement, Tianjin Agricultural University, Tianjin 300384;College of Food Science and Biological Engineering, Tianjin Agricultural University, Tianjin 300384;Tianjin Engineering and Technology Research Centre of Agricultural Products Processing, Tianjin 300384)

机构地区：[1]山西农业大学食品科学与工程学院,太谷030801 [2]天津农学院园艺园林学院,天津300384 [3]天津农学院农业分析测试中心,天津300384 [4]天津农学院食品科学与生物工程学院,天津300384 [5]天津市农副产品深加工技术工程中心,天津300384

出　　处：《食品科技》2018年第4期23-28,共6页Food Science and Technology

基　　金：国家自然科学基金面上项目(31471630)

摘　　要：通过对晚采鸭梨果实分别进行急速和缓速降温处理,并测定贮藏期间晚采鸭梨的褐变指数、CO_2和乙烯含量等生理指标以及多酚氧化酶(PPO)的活性及其相对表达量的变化,研究了缓慢降温与急速降温处理下PPO基因表达对晚采鸭梨果心褐变的影响。结果表明:缓慢降温处理的晚采鸭梨PPO活性变化趋势比急速降温处理的PPO活性平缓,在贮藏初期(30 d^60 d)缓降处理PPO活性高于急降,而贮藏初期是引起果心褐变的关键时期,缓降初期较高的PPO基因相对表达量促进了PPO活性的升高,从而导致鸭梨果心在贮藏60 d时褐变严重。说明缓慢降温处理下,PPO1和PPO2 2个基因在贮藏初期共同促进了多酚氧化酶活性的升高,从而促进果心褐变。结论:急速降温抑制了PPO基因的表达,适当延缓了PPO活性的升高,降低PPO的活性能保持晚采鸭梨较高的品质。The changes of the core browning index, respiration rate and ethylene content of Yali pear, PPO（Polyphenol oxidase） activity and PPO gene expression of the late-harvest pear under the slowly cooling and rapidly cooling were determined in the experiment. The effects of PPO gene expression on the browning of late-harvest Yali pear were studied under slowly and rapidly cooling. The results showed that the PPO activity of the pear under the slowly cooling was higher than that of the rapidly cooling fruit, and the activity of PPO changed slowly during the early storage（30 d-60 d）. During the critical period of change, the relative higher PPO gene expression under slowly cooling in the early phase accelerated the PPO activity, which resulted in core browning on the 60 days. The conclusion were as follows： rapidly cooling inhibited the expression of PPO gene, delayed the increase of PPO activity and reduced the PPO activity, which can keep the higher quality of the late-harvest pear fruit.

关 键 词：晚采鸭梨 褐变 降温方式 PPO活性 PPO基因 

分 类 号：TS255.3[轻工技术与工程—农产品加工及贮藏工程]