电导法研究盐类对黄瓜冻害的预防作用  

Prevention Effect of Salt on Cucumber Freezing Injury by Conductance Method

作　　者：连喜军[1] 杨美静[1] 刘畅[1] 王吰[1] 贾烨[1] 沈水芳[1] 

机构地区：[1]天津商业大学天津市食品生物技术重点实验室,天津300134

出　　处：《长江蔬菜》2009年第07X期33-36,共4页Journal of Changjiang Vegetables

摘　　要：选用5种无机盐常温浸泡黄瓜,以电导法测定黄瓜冻害伤害率,研究了盐的种类、盐液pH值、盐浓度、浸泡时间等因素对黄瓜冻害的影响。试验结果表明,所选5种盐KNO3,MgSO4,NaCl,CaCl2和MgCl2中,经MgCl2浸泡后黄瓜耐冻害能力最强,最佳浸泡工艺为:MgCl2浸泡浓度为0.03g/100mL,pH值8.0,浸泡时间20min。在-18℃冷冻100min后,空白组伤害率为57.8%,经MgCl2浸泡组为30.7%,伤害率降低了27.1%,抗冻害能力提高了46.8%。经浸泡后黄瓜呼吸强度明显降低,浸泡20min后黄瓜的呼吸强度由对照的33.8mg·(kg·h)-1降低到15.8mg·(kg·h)-1,显示盐类提高黄瓜抗冻害能力与降低其呼吸强度之间有一定关联。Cucumber is a kind of common vegetables in life, freezing injury of cucumber often happens in winter because of its thin pericarp and it is difficult to store for a long time. Increasing concentration of intracellular fluid and lowering of its freezing point caused by immersed in inorganic salt solutions could prevent cucumber from freezing injury. The effect of 5 kinds of inorganic salt, salt concentration, pH of solutions and time of immersing were studied in normal temperature. Freezing injury percent was regard as index by determining from conductance method. The results showed that the highest tolerant ability to freezing injury came from MgCl2 group in 5 groups of KNO3, MgSO4, NaCl, CaCl2 and MgCl2, the best treatment was as following, they were treated for 20 rain with 0.03 g/100 mL MgCl2 pH=8.0, in this case, the freezing injury percent was 30.7% after freezing in -18℃ for 100 min, which was 27.1% lower than that of the control, the freezing injury-resistant ability of cucumber increased by 46.8%. The respiration intensity of cucumber reduced greatly when it was immersed in MgCl2 solutions, the rate reduced from 33.8 mg· （kg·h）^-1 to 15.8 mg· （kg·h）^-1 when cucumber was immersed for 20 min, which indicated that there was relationship between increasing freezing injury-resistant ability of cucumber and lowering its respiration rate existed.

关 键 词：黄瓜 盐溶液 冻害 电导率 呼吸强度 

分 类 号：S642.2[农业科学—蔬菜学] S426[农业科学—园艺学]