【作者】 静玮；

【导师】 屠康；

【作者基本信息】 南京农业大学 ， 农产品加工与贮藏工程， 2008， 硕士

【摘要】 以山东烟台产,中熟甜樱桃品种“先锋”(Prunus avium L.cv.Van)为材料,探讨热水喷淋处理(Hot Water Rinsing and Brushing,以下简称HWRB处理)对甜樱桃果实采后腐烂的控制和品质的影响、对果实生理生化的作用机理以及与拮抗酵母菌结合处理对采后腐烂的控制效果。1.首次采用HWRB处理甜樱桃果实,结合国外已有的研究经验和预试验结果,选择了两个处理条件(60℃20s、65℃20s)。结果显示,60℃20sHWRB处理能有效控制果实在贮藏期的发病率和腐烂指数的上升,推迟了果梗褐变。热处理并未影响果实的外观品质,保持了较好的果皮颜色,有利于花青素的积累和维持。冷藏环境下有利于延长处理果实贮藏期,冷藏14d后果实能保持较好的货架品质,是适宜的贮藏时间。2.60℃20sHWRB处理通过保护果实活性氧代谢平衡和防御体系活力来延缓果实的衰老:该处理在一定程度上降低了呼吸强度,保持了较高的SOD、CAT酶活性和ASA含量,抑制了果实丙二醛(MDA)含量的增加,保持了果实细胞膜的完整性;对POD、PPO有一定的抑制效果,利于控制果实的褐变,延缓了果实的衰老;同时该处理保持了较高的PAL酶活性,这有利于增强果实自身的抗病性。3.65℃20sHWRB处理对樱桃果实会造成一定的热伤害,表现为部分果实果皮的皱缩褐变,并且MDA含量和呼吸强度始终高于对照,同时该处理组的SOD、CAT和PAL酶活性较低,未能抑制POD、PPO的活性。虽然该处理抑制了果实的部分腐烂,但总体上不适合樱桃果实的采后保鲜处理。4.60℃20s HWRB处理能够杀死或钝化樱桃果实表面的大量微生物,同时对人工接种两种致病菌(扩展青霉、灰葡萄孢霉)的孢子萌发也有显著抑制效果,从而减少了果实腐烂或伤口病害的发生发展。另外,HWRB处理在接种致病菌24h内均能有效控制腐烂的发生,其中接种6h后进行处理能够完全抑制伤口发病,而接种12h后再处理的伤口发病也较低。5.将60℃20s HWRB处理结合罗伦隐球酵母菌能够进一步抑制樱桃果实的自然发病率,处理效果好于单独处理,同时并未影响果实的外观食用品质;另外,结合处理有效减少了人工接种两种致病菌(扩展青霉、灰葡萄孢霉)所引起的伤口腐烂,并且接种灰葡萄孢霉的伤口在结合处理后完全不发病,进一步证明了结合处理的作用效果。更多还原

【Abstract】 The middle-mature sweet cherry fruits(Prunus avium L.cv.Van) were treated by postharvest hot water rinsing and brushing(HWRB) treatment and the effect of HWRB treatment on decay and quality,mechanism of physiology and biochemistry,and combinations of HWRB treatment and yeast antagonist on fruits were investigated.1.HWRB treatment was first used for sweet cherry fruits postharvest treatment refereed foreign studies.HWRB treatments at 60℃or 65℃for 20s were chosen for study referring to foreign research resuits and pre-experiment.Results showed that,60℃20s HWRB treatment could effectively reduce fruits decay and its development and delay stem brown. Fruit quality during storage was not affected by HWRB treatment which maintained fruit surface color and help accumulating the content of anthocyanins.Low temperature was benefit for keeping longer storage time and 14 days’ storage was fit for good quality at shelf life.2.Balance of ROS(reactive oxygen species) metabolism and activity of resistance system were protected by 60℃20s HWRB treatment in order to delay fruit senescence.HWRB treatment reduced fruits respiration rate,kept high activity of SOD and CAT and content of ASA,and decreased contents of MDA as a result of maintaining cell membrane stability; Activities of POD and PPO were partly inhibited by HWRB treatment which help controlling fruits brown and delay senescence;High activity of PAL which be maintained by HWRB treatment could enhance resistance.3.65℃20s HWRB treatment might cause heat damage on sweet cherry fruits.Parts of treated fruits showed surface shrinking and brown;Contents of MDA and respiration rate of 65℃20s HWRB treated fruits were higher than the control.Activities of SOD,CAT and PAL were low but activities of POD and PPO were not inhibited.Though 65℃20s HWRB treatment reduced parts of fruits decay,but anyway this temperature was not fit for sweet cherry fruits postharvest fresh-keeping.4.60℃20s HWRB treatment could significantly killed or inactivated a large number of the epiphytic microbial population on fruit surface and inhibited germination of pathogen spores(Penicillium expansum and Botrytis cinerea) so as to reducing fruits natural decay and controlling the development of infected wounds.60℃20s HWRB treatment after inoculation with pathogen spores decreased infected wounds within 24h;Especially, HWRB treatment 6h after inoculation gave the lowest germination and completely inhibited wounds decay while 12h after inoculation also got low infected wound of fruits.5.Treating fruits with 60℃20sHWRB treatment and then dipping them into a cell suspension of C.laurentii showed the lowest fruit natural decay than separate treatment, and not affected fruits quality.Otherwise,the combination of HWRB and C.laurentii effectively controlled infected wounds that inoculated with two pathogen spores (Penicillium expansum and Botrytis cinerea) and completely controlled that with Botrytis cinerea which confirm the effect of combination treatments again.更多还原