【作者】 杨文侠；

【导师】 高振江； 童军茂；

【作者基本信息】 中国农业大学 ， 种植业， 2005， 硕士

【摘要】 本研究围绕新疆哈密瓜保鲜研究这一中心课题,对哈密瓜贮藏期间主要致腐菌种类及壳聚糖对其抑菌效果进行了实验研究,并以壳聚糖涂膜处理哈密瓜进行贮藏试验,测定了涂膜与未涂膜处理的哈密瓜在贮藏期间发生的多项生理生化变化,对涂膜保鲜效果进行详细的研究。 从腐烂的哈密瓜皮上观察到,感染的腐烂霉菌主要是交链孢菌(Alternaria)和青霉菌(penicillium),通过抑菌试验,筛选出柠檬酸和醋酸作为壳聚糖溶剂其抑菌效果均较为理想,酸的种类和浓度与壳聚糖有协同作用,2%壳聚糖-2%醋酸溶液能够有效抑制混合菌的生长繁殖。 试验通过对贮藏期间常温(23℃～30℃)和低温(3℃～5℃)条件下,涂膜和未涂膜两组的哈密瓜失重率、腐烂率、呼吸强度、果肉硬度、可溶性固形物含量、还原糖含量、Vc含量、总酸度、pH值、乙醇、总果胶和水溶性果胶含量、相对电导率和多酚氧化酶(PPO)与过氧化物酶活性(POD)的测定,结果表明,哈密瓜经壳聚糖涂膜处理,其生理生化指标变化趋势,有助于耐藏性的提高,保鲜效果明显优于未经涂膜处理的对照组,论证了这项技术在哈密瓜保鲜中的可行性。 通过研究壳聚糖涂膜保鲜试验效果证明,哈密瓜进行涂膜保鲜可以有效地抑制微生物腐败,降低腐烂率,延长贮藏期,是哈密瓜采后商业化可行的一项措施。更多还原

【Abstract】 This paper’s main objective was improved the storage life of Xinjiang Hami melon. The bacteria were separated and antistaling mechanism on Xinjiang Hami melon was studied using chitosan. The effect of preservation of Xinjiang Hami melon treated with chitosan film was studied. The main results of this paper are as follows:It was separated and determined from the rotten Hami melon skin that the infection rotten mold mainly is alternaria and penicillium. Citric acid and acetic acid were ideal solvent, its were cooperated with chitosan. The growth and breeding of bacteria can be suppressed effectively by use of the chitosan solution.The Hami melon was stored at constant temperature (23℃~30℃) and low temperature (3~5℃), at the same temperature, the melon was treated with and without the film respectively. The weightlessness rate, decay rate, breath intensity, fruit pulp degree of hardness、 soluble solid line of content、 return to original state sugar content, Vc content、 total acidity、 pH value、ethyl alcohol、 total pectin and water-soluble pectin content , relatively electrical conductivity, polyphenoloxidase (PPO) and peroxide enzymic(POD) activity was determined during the storage. The test result indicates: The quality of Hami melon that was treated with chitosan film was better than that of no treated , and the storage time was relatively longer.The effect was proofed by the experiment, it can draw a conclusion that the Hami melon using the chitosan film can separate the deleterious microorganisms, reduce the decay rate, lengthen storage time. So it has considerable feasibility to post-harvest commercial treatment.更多还原