摘要
目的:快速找到青菜冷处理的临界点温度。方法:使用叶绿素荧光仪和离子选择性电极测定不同温度冷水处理的青菜。结果:青菜叶片用冷水处理1 min,在-4℃检出低温伤害,显示处理时间不够。冷水处理青菜10 min,可以判断冷害温度,而不足以激发显著的冷激反应。在0℃时,ETR和qP下降极显著,Y(NO)显著上升。在2℃时,所有荧光参数正常,属于安全温度。处理30 min时,2℃处理的NPQ和qN显著上升,有明显的冷激反应。0℃处理30 min后K^+溶出极显著上升(P<0.01),说明细胞膜渗漏加剧,青菜在0℃下贮藏可能有冷害。0~2℃处理Ca^2+溶出显著上升,说明已引起细胞壁的变化。Na^+溶出随温度下降而下降,0℃处理Na^+的溶出最少。结论:ETR和K+溶出可作为冷害指标,NPQ和qN可作为冷激温度和时间的指标。0℃冷水处理10 min或30 min均可以检出低温伤害,青菜在0℃下长期贮藏可能有冷害,2℃处理30 min有冷激反应,在该温度可以安全贮藏。1℃是两者的临界点。
Objective:In order to find rapid assessment of critical point temperature for cold shock treatment and low temperature storage.Method:After pak choy(Brassica rapa var chinensis)dipped in different temperatures of cold water,the leaves were measured by chlorophyll fluorescence analyzer,and the osmosis and diffusion amount of potassium(K+),calcium(Ca2+)and sodium(Na+)were determined by ion electrodes.Result:Pak choy was dipped in cold(or salt)water for 1 min,all fluorescence data did not significantly change until treatment temperature dropped to-4℃.Obviously,the dipping time of 1 min for judging chilling injury temperature was not enough.When pak choys were treated with 0℃water for 10 min,all parameters had significantly changed.Especially,ETR and qP had extremely significant decrease,while Y(NO)was significant increase.When pak choys were treated with 2℃water for 10 min,all fluorescence data did not show significantly change,so 2℃was identified as a non-hazardous temperature,and treatment for 10 min was enough time for judging chilling injury temperature,but not enough for judging cold shock response temperature.When leaves treated by 2℃water for 30 min,Stern-Volmer type NPQ and qN were significantly increased,and obvious cold shock response were observed.The diffusion and osmosis content of K+treated with 0℃water for 30 min were extremely significantly higher than that of 4℃(P<0.01),which showed that cell membrane leakage was exacerbated,and pak choy might suffered chilling injury at 0℃.The diffusion amounts of Ca2+from pak choy treated with 0-2℃was exceeded than that of 4℃,which meant low temperature might induce the changes of the calcium binding capacity of cell walls.The diffusion of Na+decreased with the dropping of temperature,and Na+of 0℃treatment was significantly lower than that of 4℃(P<0.05).Conclusion:ETR data and diffusion and osmosis content of K+can be used as parameters for judging chilly injury temperature,NPQ and qN can be used as parameters for judging the temperature an
作者
顾双
王向阳
Gu Shuang;Wang Xiangyang(College of Food and Biological Engineering,Zhejiang Gongshang University,Hangzhou 310018)
出处
《中国食品学报》
EI
CAS
CSCD
北大核心
2019年第10期190-196,共7页
Journal of Chinese Institute Of Food Science and Technology
基金
浙江省食品科学与工程“重中之重”一级学科基金项目(JYTSP20141101)
浙江省公益技术研究项目(LGN18C200014)
关键词
青菜
叶绿素荧光参数
低温伤害
冷激处理
离子电极
pak choy
chlorophyll fluorescence parameters
low temperature damage
cold shock treatment
ion-selective electrode
