不同预冷降温速度对减轻桃果实采后机械伤的影响

桃果实营养丰富,易于消化吸收,深受消费者喜爱。但桃果实采后易遭受机械伤,导致腐烂损耗,严重影响商品价值。本实验以‘湖景蜜露’桃为材料,并对其进行不同降温速度的预冷处理(果心温度在3 h或16 h内从27℃降至9℃),以不进行预冷处理的材料为对照(Control check,CK),然后再对桃果实进行挤压机械伤处理(通过质构仪模拟挤压处理,探头直径100 mm,测试深度10 mm,挤压速度1.5 mm/s),以研究不同预冷降温速度对减轻桃果实采后贮藏物流过程中遭受机械伤的影响。结果表明,对桃果实进行预冷处理,尤其是3 h快速预冷处理,可以降低果实瘀伤指数、腐烂率和失重率,延缓果实硬度下降,并且还会加速苯丙氨酸裂解酶活性在贮藏后期的上升。其中经过3 h的快速预冷处理,果实瘀伤指数和腐烂率相较CK分别降低了11.7%和8.3%。预冷处理还可抑制桃果实因遭受机械伤而导致的呼吸速率、乙烯释放量、丙二醛含量和多酚氧化酶活性的上升,其中3 h快速预冷处理和16 h慢速预冷处理在贮藏21 d时的多酚氧化酶活性分别为CK的75.7%和72.1%。此外,预冷处理也会延迟总酚含量的上升,两个预冷处理组在贮藏...     

臭氧结合气调冷藏对草莓保鲜品质的影响

草莓是一种易腐水果,贮藏期的失水、腐烂和软化严重影响了草莓的品质。采用臭氧处理介导的气调贮藏草莓果实,观察其对草莓贮藏保鲜品质的影响。首先,通过实验确定了草莓臭氧处理的最佳浓度为30 mg/m3,处理时间为30 min。分析了3种不同贮藏方式下(单独冷藏为对照,气调箱包装冷藏和臭氧处理结合气调冷藏)样品在18 d贮藏期内的腐烂率、可滴定酸、可溶性固形物、丙二醛含量等指标的变化情况,结果显示臭氧结合气调贮藏组及气调贮藏均能显著延缓草莓在贮藏过程中的品质降低,18 d后这2组草莓果实其腐烂率、SSC含量、MDA含量均低于对照组,而硬度和TA含量均高于对照组,臭氧结合气调贮藏组的各项品质指标最好,说明臭氧对气调保鲜具有增效作用。该研究结果有利于进一步改进草莓采后保鲜措施,提高草莓商品价值,具有一定应用前景。     

蜂胶提取物对草莓室温保鲜效果的研究

为研究蜂胶乙醇提取物对草莓室温下的保鲜作用,以1%、2%、4%、6%浓度的蜂胶提取物作为保鲜剂,对草莓进行涂膜并在室温(24.5℃±)条件下贮藏,对不同涂膜处理后的草莓进行硬度、呼吸强度、可溶性固形物含量、可滴定酸含量、Vc含量、失重率、腐烂率等生理指标的测定。结果表明:在室温(24.5℃±)条件下,2%蜂胶提取物可以显著降低果实的呼吸强度、失重率和腐烂率,有效保持果实硬度,延缓可溶性固形物的降解,延缓果实可滴定酸和Vc含量的下降速度,维持果实原有品质,延缓果实成熟衰老。     

油菜素甾醇对章姬草莓贮藏品质的影响

目的 探讨章姬草莓果实的贮藏特性与油菜素甾醇(brassinosteroids, BRs)的关系。方法 以章姬草莓为供试材料, 以蒸馏水为对照, 通过不同浓度的BRs溶液(5、10、15 μmol/L)喷洒草莓果实, 观察BRs对其失重率、腐烂情况等贮藏品质的影响。结果 经过BRs处理章姬草莓果实后质量损失明显降低, 腐烂速度减缓, 特别是在10 μmol/L浓度喷洒下章姬草莓果实失重率、可溶性固形物和维生素C (vitamin C, VC)含量的损失均显著低于对照组。在第6 d时, 10 μmol/L BRs处理组章姬草莓果实比对照组的VC含量高1.8倍, 硬度高19.2%; 腐烂率、腐烂指数、丙二醛含量的增加量均显著低于对照组(P<0.05); 对照组比10 μmol/L BRs处理组章姬草莓果实丙二醛含量高1.27倍, 腐烂率高13%, 腐烂指数高20%。结论 10 μmol/L BRs喷洒下对延长章姬草莓果实的贮藏时间具有较好的效果。     

热处理对袋装草莓果保鲜效果的影响

研究了袋装草莓果经 40℃热处理后在室温 ( 2 2± 2 )℃贮藏过程中呼吸强度和化学成分的变化。结果表明 ,热处理可降低草莓果贮藏期间的腐烂率和减少抗坏血酸、还原糖和有机酸含量的损失。以热处理 3 0min的效果最明显 ,且对草莓呼吸的刺激作用最小     

1-MCP和预贮对深州蜜桃采后生理和品质的影响

为保持深州蜜桃冷藏期间良好的品质, 延长贮藏时间, 采用1 . 0 μ L / L 1 - 甲基环丙烯
（1-methylcyclopropene,1-MCP）熏蒸和预贮（8 ℃、5 d转入0 ℃）的方法对采后深州蜜桃进行处理,测定0 ℃冷
藏期间果实呼吸速率、乙烯释放速率和品质的变化。结果表明,1-MCP处理能够明显抑制桃果实冷藏期间的呼吸速
率和乙烯释放速率,推迟呼吸高峰期的出现;同时延缓了果实软化,抑制可溶性固形物含量上升,降低了果实的褐
变指数和腐烂指数;预贮促进了果实后熟,但预贮和1-MCP处理均明显降低了贮藏期果实褐变度和酚类物质含量,
二者结合处理对抑制果实褐变效果最佳。     

热处理与贮藏温度对草莓果实保鲜效果的影响

以大棚新鲜草莓为实验材料,分别研究2种热处理方式(40℃热空气,15min和40℃无菌水,15min)以及不同贮藏温度(常温20℃和低温4℃)对草莓的腐烂率、失重率的影响。结果表明,热处理明显有利于草莓的保鲜,其中热空气处理优于热水处理,低温贮藏优于常温贮藏。基于这一结论后,又以相同的新鲜草莓为实验材料,研究3种不同温度(35、40、45℃)的热空气和不同时间(10、15、20min)处理对草莓色泽、气味、硬度、酸度、糖含量以及呼吸强度的影响。结果表明,热处理能明显影响草莓贮藏期的生理和品质,热处理可保持草莓贮藏过程中的色泽、气味、硬度,降低其呼吸强度,减少草莓果实中糖和酸的损失,延缓草莓衰老。其中以45℃热空气处理10min保鲜效果最好。     

复合凝胶膜对草莓保鲜作用的研究

以食用安全的多种食品添加剂材料在草莓表面形成复合凝胶膜(MGF),4μm厚的聚乙烯薄膜袋包装,(20±1)℃室温贮藏.检测了果实硬度、电导率、光泽度、呼吸速率、失水率、腐烂率和总体可接受度在贮藏过程的变化趋势.与未涂膜的对照果相比,涂膜草莓软化和电导率上升的速率减缓;色泽稳定;呼吸活性降低.对照果实至第5天全部腐烂,涂膜草莓到第6天失水率3.04％、腐烂率8％、总体可接受度90.28％.MGF显著延长草莓在常温条件的保鲜期.     

不同冷藏处理对蟠桃生理品质的影响

为提升蟠桃(Prunus perisica L.)果实冷藏品质,研究了将蟠桃直接置于0℃和预贮6℃5 d后结合不同包装处理(对照、气调包装、气调包装结合乙烯吸收剂)后置于0℃贮藏期间果实品质变化。结果表明,与其他处理相比,预贮结合自发气调及乙烯吸收剂处理可以保持蟠桃果实糖酸及硬度,可以有效维持果实较低的呼吸强度,提高果实中可溶性固形物含量,显著(p0.05)降低果实腐烂率。     

O_3处理对草莓果贮藏品质的影响

以草莓果 (丰香 )为试材 ,经O3 处理 3～ 6min后 ,在 (2 0± 1)℃下贮藏 4d ,探讨O3 处理对草莓果贮藏品质的影响。结果表明 ,O3 处理 3min有利于降低草莓果呼吸强度和腐烂率 ,减少可溶性固形物、有机酸和抗坏血酸含量损失 ;花青素含量随草莓的硬度降低而增加。     

柠檬酸处理对采后芒果保鲜效果的影响

为探索芒果采后果实保鲜新方法,“台农一号”芒果采后分别经0(对照)、5、10mmol/L 柠檬酸浸果10min后,常温贮藏,定期检测果实的常规品质、成熟进程和病情发展的变化。结果表明：柠檬酸处理使果实软化、果肉可溶性固形物增加及可滴定酸含量降低的速率减缓,果实的转黄指数和病情指数降低,说明适当水平的柠檬酸处理能有效延缓芒果采后果实的成熟进程,并且抑制果实腐烂发生。柠檬酸处理是芒果采后贮藏保鲜的一种可选新方法。     

利用拮抗菌常温保鲜凤凰水蜜桃效果系统研究

由于使用化学保鲜剂对环境和人体存在危害,故观测和比较了两种病原菌拮抗菌——罗伦隐球酵母(Cryptococcus laurentii)和枯草芽孢杆菌(Bacillus subtilis)单独使用和与化学试剂(2%NaHCO3)配合使用对张家港市凤凰水蜜桃(Prunus persica)采后保鲜品质的影响。实验采取直接浸果的方式,果实处理后装入保鲜袋置于常温条件下(25℃),放置5d后测量其失重率、腐烂程度、硬度、可溶性固形物含量、呼吸强度、相对电导率、丙二醛(MDA)含量和多酚氧化酶(PPO)含量8种生理指标。结果表明:单独使用拮抗菌液的处理组果实保鲜效果最佳,其中枯草芽孢杆菌效果尤为显著;单独使用化学试剂处理组保鲜效果最差,二者结合处理组的效果居中。因此,对凤凰水蜜桃而言,拮抗菌制剂是比化学试剂NaHCO3更为有效且无污染的生物保鲜剂,适宜推广应用。     

Effect of yeast antagonist in combination with heat treatment on postharvest blue mold decay and Rhizopus decay of peaches

The potential of using heat treatment alone or in combination with an antagonistic yeast for the control of blue mold decay and Rhizopus decay of peaches caused by Penicillium expansum and Rhizopus stolonifer respectively, and in reducing natural decay development of peach fruits, as well as its effects on postharvest quality of fruit was investigated. In vitro tests, spore germination of pathogens in PDB was greatly controlled by the heat treatment of 37 degrees C for 2 d. In vivo test to control blue mold decay of peaches, heat treatment and antagonist yeast, as stand-alone treatments, were capable of reducing the percentage of infected wounds from 92.5% to 52.5% and 62.5%, respectively, when peach fruits stored at 25 degrees C for 6 d. However, in fruit treated with combination of heat treatment and Cryptococcus laurentii, the percentage of infected wounds of blue mold decay was only 22.5%. The test of using heat treatment alone or in combination with C. laurentii to control Rhizopus decay of peaches gave a similar result. The application of heat treatment and C. laurentii resulted in low average natural decay incidences on peaches after storage at 4 degrees C for 30 days and 20 degrees C for 7 days ranging from 40% to 30%, compared with 20% in the control fruit. The combination of heat treatment and C. laurentii was the most effective treatment, and the percentage of decayed fruits was 20%. Heat treatment in combination with C. laurentii had no significant effect on firmness, TSS, ascorbic acid or titratable acidity compared to control fruit. Thus, the combination of heat treatment and C. laurentii could be an alternative to chemicals for the control of postharvest decay on peach fruits.     

褪黑素结合丁香酚处理对红桃贮藏品质的影响

为研究褪黑素结合丁香酚处理对桃贮藏品质的影响,本实验以镇远红桃为试验材料,采用不同的处理（0.5 mmol/L褪黑素处理;50 μL/L丁香酚处理;0.5 mmol/L的褪黑素+50 μL/L的丁香酚处理）对桃浸泡5 min,处理后自然晾干在温度（0.5±0.5）℃条件下进行贮藏,研究贮藏期桃品质变化。结果表明:褪黑素结合丁香酚的处理能有效地降低果实腐烂率和呼吸强度,延缓硬度、可溶性固形物含量、可滴定酸含量和总酚含量的下降,有效维持SOD活性、APX的活性和PPO的活性。在贮藏期60 d时,褪黑素+丁香酚组果实腐烂率仅为14.65%,而CK组、褪黑素组、丁香酚组的果实腐烂率分别为36.72%,25.63%,22.49%。综上所述,褪黑素结合丁香酚处理能够推迟桃贮藏期的衰老进程,抑制果实品质的下降,更好地保持贮藏品质。     

真空预冷处理对鲜切猕猴桃品质的影响

为延长鲜切果蔬的货架期,选取浆果类——猕猴桃为研究对象,研究真空预冷处理对鲜切猕猴桃贮藏品质的影响。结果表明:与对照组相比,真空预冷能够很好地起到保鲜鲜切猕猴桃的作用;其中预冷终温为2℃的鲜切猕猴桃在贮藏末期(6 d)的综合品质优于其它处理,其失重率为11.08%;果肉、果心硬度下降率分别为45.19%和33.98%;VC含量和色差ΔEab值与对照组差异明显。     

臭氧处理对新疆厚皮甜瓜贮藏品质和生理特性的影响

研究4 种不同贮藏条件（－1～0 ℃条件下5×10－6 m3/m3（以空气计）臭氧处理和5～6 ℃条件下2×10－6、4×10－6 m3/m3臭氧及2%～5% O2结合2%～4% CO2处理）对新疆厚皮甜瓜贮藏品质和生理特性的影响,贮藏过程中每15 d测定呼吸强度、乙烯释放速率、可溶性固形物含量、可滴定酸含量、pH值、果肉硬度、还原糖含量和过氧化物酶（POD）活性;贮藏68 d统计所有处理组甜瓜的腐烂和冷害情况。结果表明：低温冷藏（－1～0 ℃）条件下的甜瓜呼吸强度最低,但是出现了冷害现象,68 d时冷害指数为39%;贮藏于5～6 ℃条件下每日通入30 min2×10－6 m3/m3臭氧气体的甜瓜贮藏效果好于对照组,贮藏于5～6 ℃条件下每日通入30 min 4×10－6 m3/m3臭氧气体的甜瓜贮藏效果最好,其中呼吸高峰延迟出现,且呼吸强度降低,同时乙烯释放速率最小,还原糖含量、果肉硬度和POD活性较高,68 d时的腐烂指数仅为0.318;5～6 ℃环境下的气调（2%～5% O2）甜瓜可滴定酸含量最高,与其他处理组的差异性极显著（P＜0.01）;对照果实贮藏效果最差。     

加热预处理对青梅低温贮藏品质的影响

将绿熟期青梅用30℃热风分别处理24、48h后,与无处理果实一起,在青梅冷害发生临界温度5℃下贮藏,通过测定贮藏期间青梅的乙烯生成量、呼吸速率以及主要化学成分的变化,探讨加热预处理对减轻青梅冷害的效果及对果实贮藏品质的影响。结果表明:经30℃-48h处理虽然在减轻冷害方面表现出一定效果,但该处理果实的硬度下降较快,外观颜色的黄化进展也明显快于30℃-24h处理和对照,且贮藏后期腐烂较严重,果实的贮藏期只有36d;30℃-24h加热预处理可有效抑制青梅冷害的发生,其它贮藏品质指标也较好,果实的贮藏期可达到50d,比无处理果延长了7d。     

Study on the efficiency of ethylene scavengers on the maintenance of postharvest quality of tomato fruit

The objectives of this study were to achieve the best level of each ethylene scavenger and evaluate the effect of selected levels of treatments on some quality traits of tomato during storage. Tomato fruits were subjected to four levels of treatments: palladium-promoted nano zeolite, KMnO₄-promoted nano zeolite, 1-MCP, CaCl₂, salicylic acid (SA) and UV-C. The sampling was done at 0, 7th, 14th, 21st, 28th and 35th days of cold storage. The results showed that palladium-promoted nano zeolite 5%, KMnO₄-promoted nano zeolite 20%, 1-MCP 30 ppm, CaCl₂ 2%, SA 1% and UV-C 15 min levels had the most ethylene scavenging function. Effectiveness of the treatments in ethylene scavenging was in the order: palladium?>?KMnO₄?>?1-MCP?>?SA?=?CaCl₂?>?UV-C. The palladium-promoted nano zeolite 5% had more positive effects on phenol content, polygalacturonase activity, lycopene content, fruit firmness and weight loss, and UV-C 15 min had effect on decay severity as compared to the other treatments. Overall, palladium-promoted nano zeolite 5% could be considered not only as favorable tool in tomato shelf life extension but also in preservation of quality characteristics of tomato fruits during storage. Moreover, the UV-C 15 min treatment could be an effective method for reducing decay severity and maintaining postharvest quality of tomato fruits.     

Enhanced preservation effects of sugar apple fruits by salicylic acid treatment during post‐harvest storage

BACKGROUND: Salicylic acid (SA) is recognised as an endogenous signal, mediating in plant defense and against pathogens. It has been reported that SA treatment can reduce decay and extend storage life of various fruit, such as bananas, peaches and apples. RESULTS: Physiological and biochemical responses in harvested sugar apple fruit (Annona squamosa L.) to SA at 0.4, 0.8 and 1.2 mmol L^?1 were investigated during post‐harvest storage. Results indicated that SA treatments lowered respiration, increased activities of antioxidant enzymes of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX), decreased lipoxygenase (LOX) activity and correspondingly lowered Malondialdehyde (MDA) contents in treated fruits was observed as compared to the control. Moreover, production of superoxide free radical (O₂^{?, ?}) and ethylene was significantly decreased in the treated fruits. Total soluble solids, total soluble sugar, softness and decay rate were significantly lowered in treated fruits, and in turn a delay in the fruits ripening process was achieved after 10 days of storage. CONCLUSION: SA has positive effects in maintaining membrane integrity and in delaying fruit ripening process, which results in improved storability of sugar apple. Copyright © 2008 Society of Chemical Industry