[关键词]
[摘要]
为了研究不同贮藏温度对黄瓜品质及细胞结构的影响,本试验以申青黄瓜为研究对象,将黄瓜置于2 ℃、8 ℃、12 ℃、20 ℃下贮藏,每隔2 d测定其感官评分、褐变指数、硬度、电解质外渗率、降温曲线、细胞间隙等指标的变化。结果表明,在2 ℃下,随着贮藏时间的延长,感官评分逐渐减低,10 d时黄瓜品质开始变差,褐变指数逐渐增大,12 d时达到71%,硬度逐渐降低,12 d时部分出现腐烂,硬度相比于0 d时下降了43.88%,此时,电解质外渗率增幅已经达到40%,而12 ℃和20 ℃则无明显品质变化。利用果蔬冰点及过冷点测试装置测得黄瓜组织降温曲线,温度越变过程提前,降至过冷点的平均速度提高,不同贮藏时间下黄瓜的冰点基本都在-2 ℃左右。通过观测黄瓜组织细胞间隙的变化,发现细胞间层厚度逐渐增大,2 ℃下贮藏10 d,L1达到3.307 μm,相应的细胞次生壁厚度逐渐减小,L3达到4.233 μm。
[Key word]
[Abstract]
The impact of storage under different storage temperatures on quality and cell structure of Shen Qing cucumbers was investigated. Cucumbers were stored at 2 ℃, 8 ℃, 12 ℃, and 20 ℃ and changes in sensory evaluation, index of internal browning, firmness, cooling curve, and intercellular layer thickness were analyzed. The results showed that at 2 ℃, with an extension of storage time, sensory parameters deteriorated, the quality of cucumber fruits decreased, the index of internal browning reduced to 71% after 12 days and some cucumber fruits began to decay. The firmness decreased to 43.88%, while electrolyte leakage increased by 40%. On the other hand, the cucumber fruits did not show any symptoms of deterioration at 12 ℃ and 20 ℃. The cooling curve showed that, with an extension of storage time, the point of temperature jump moved up and the average speed that dropped to the supercooling point increased as well. The freezing point of cucumber fruits was approximately -2 ℃ regardless of storage time. Changes in cell structure indicated that the intercellular layer thickness increased and reached 3.307 μm at 2 ℃ after 10 days; meanwhile, the secondary wall thickness decreased and reached 4.233 μm.
[中图分类号]
[基金项目]
国家自然科学基金资助项目(31371526):低温逆境下冷敏果实机体传热特性与组织冷损伤相关性研究