【作者】 李学智；

【导师】 吕家龙； 徐志豪；

【作者基本信息】 浙江大学 ， 蔬菜学， 2003， 硕士

【摘要】 本试验以黄秋葵品种‘纤手’为试验材料，研究了黄秋葵荚果发育时期，特别是荚果食用品质形成期间，果实的形态、营养成分的变化，及其采收适朋形态与相关生理生化指标的关系，以及采后黄秋葵贮藏过程中，温度和壳聚糖涂膜对黄秋葵采后贮藏的影响。结果表明，随着黄秋葵开花后时间的延长，荚果的食用品质存在着明显的变化，采收不及时，黄秋葵荚果极易纤维化，失去食用价值；采收过早又显著降低产量。黄秋葵采后的贮藏试验表明：低温和壳聚糖处理能有效的保持黄秋葵采后的品质。 本文重点研究了黄秋葵花谢后11天内荚果食用品质形成期间，各种营养成分的变化规律。研究结果表明，黄秋葵嫩荚在不同的采收期，荚果长度、直径、重量在生长初期呈明显的持续上升趋势，开花第九天后长度、直径、重量的增长才趋缓。可溶性蛋白质含量在花后第九天前呈一直下降趋势，但是前五天的下降量不大，第九天后荚果中可溶性蛋白质含量又有所上升。蔗糖、总糖呈先下降后上升的变化，还原糖则一直下降，果糖的含量略有变动，在荚果发育的各个阶段变化不大。总叶绿素含量总体上呈下降趋势，在第七天略有上升。黄秋葵荚果中粘性物质的粘度呈先上升至花后第五天达最高而后下降的变化。粗纤维含量在花后五天内呈缓慢的上升，花谢五天后荚果内粗纤维含量急剧上升。黄秋葵荚果中多数矿物元素随生长天数的增加含量呈下降趋势，但是变化不大，黄秋葵荚果富含钾、钙、镁、硫、磷等元素，还含有硒、钼等有益微量元素，而铅、砷等重金属元素的含量极低，未达到有害程度。综合本研究以上结论，花谢后5-7天左右是保持黄秋葵嫩荚食用品质，且能保证较高产量的最佳时期。 本文还研究了温度及壳聚糖涂膜处理对黄秋葵采后贮藏期间品质和生理变化的影响。结果表明：低温结合壳聚糖涂膜处理在抑制黄秋葵荚果叶绿素的降解和纤维化中效果还是比较明显的，而低温和壳聚糖涂膜对荚果中的可溶性蛋白质和各种糖分的影响不明显，但是低温和壳聚糖涂膜还是有效地保持了贮藏期间果实中各种清除自由基的酶类的活性。高温(20℃)下先聚糖处理的果实中叶縁素、可溶性蛋白质、总糖的含量高于对照，还原糖、果糖的含量略高于对照，果实的纤维化明显慢于对照，各种清除自由基的酶的活性高于对照。在三种贮藏温度下，不管是壳聚糖涂膜处理的果实，还是对照果实，与膜质过氧化有关的MDA的含量变化趋势基本一致，相同贮藏时间的果实中MDA含量在11℃和20℃都高于对照，但是壳聚糖涂膜处理并没有明显的抑制MDA的上升。壳聚糖涂膜处理在低温下效果不明显，而在高温下的效果更明显，其价值在于无法采取低温的时空条件下，可以考虑应用壳聚糖涂膜处理，具体方法有待进一步的研究。更多还原

【Abstract】 Okra (Hibicus esculenuts L. ) is one of popular vegetables in the world, especially in tropical and subtropical areas. Okra is cultivated mainly for its ’pods’ which are cooked and eaten, although in some countries the young leaves are cooked also. Tender okra is a popular ingredient of soups and stews where a highly viscous consistency is desired. Okra not only serves as a thickening agent for soups and stews, but is an important source of nutrients in the diet. In addition to its being a good source of a viscous mucilage, okra also provides fiber and protein. It was conducted to study in detail the growth pattern of okra (cv. xianshou) pods after flowering, and chemical and physical changes between flowering and harvesting maturity were studied to determine the optimum harvesting stage. Fresh okra pods have a short post harvest life, being prone to physical and physiological changes that reduce quality. Fresh okra has a high respiration rate and is extremely perishable. Quality loss in harvested okra is usually manifested as shriveling, toughening, and chlorophyll degradation. Post harvest treatment of chiston coating have been used to study the quality and physiological changes of fresh okra in storage. The results were reported as follows:1.The quality of okra pods has significant difference at different stage after anthesis. The pods in 5 days after anthesis maintain higher soluble protein content, which decreased quickly after 5th day and then increased a little.The mucilage viscosity was higher at pll value 6-8, it showed that pH value of crude extract of okra pods in di fferent stage after flowering were about 6-7, the mucilage viscosity of the pods is highest in 5th day after anthesis, with pods development mucilage viscosity decreased quickly. Okra pods maintained lower crude fibre content in 5 days after anthesis, and then crude fibre content inereased quickly. Most of mineral elements in okra pod declined in the growth period. Mucilageand fibre content are main quality factor of okra pod , according to the content of Mucilage and fibre content at different stage after anthesis, we concluded that Harvesting maturity occurred about 5 days after flowering.2.Fresh okra pods harvested at six days after anthesis were stored for 12 days in 20 , 11 , 4 with0, 0. 5%, 1% chiston spraying to study the quality and physiological changes. The results suggested that chiston coating and low temperature are effective to restrain chlorophyll degradation and raise of crude fibre, and not distinct on soluble protein and sugar changes. But in storage chiston coating and low temperature could maintain the activity of enzyme such as SOD, POD, CAT. In 20 , tin-effects of chiston coating are better than control. In20 , the content of chorophyll, soluble protein, total sugar, deoxide sugar and frotuse are higher than that of control.更多还原