不同厚度PE膜包装对核桃果实采后生理与鲜贮的效应  

Effect of Modified Atmosphere Packaging with Different Thicknesses of PE Films on Postharvest Physiology and Preservation of Green Walnut Fruit

作　　者：冯文煜[1] 蒋柳庆[1] 马惠玲[1] 马艳萍[1] 朱旭[1] 

机构地区：[1]西北农林科技大学生命科学学院,陕西杨凌712100

出　　处：《食品科学》2013年第18期295-300,共6页Food Science

基　　金：陕西省农业攻关项目(2012K01-29);陕西省自然科学基金项目(2011JQ3002)

摘　　要：为了获得核桃青果更加确切的自发气调（MA）包装技术参数，以‘西扶二号’核桃青果为材料，采取PE30（30μm）、thk．PE（459m）、PE50（50μm）3种不同厚度薄膜包装处理，以地膜（6μm）包装为对照，0～1℃贮藏条件下，跟踪测定贮藏过程中袋内气体浓度、果实呼吸速率、乙烯释放量，统计果实保鲜情况，测定贮藏前后果实含水量、核仁品质。结果表明：各包装处理均延缓了第1次呼吸高峰的到来，抑制了第2次呼吸高峰和乙烯释放高峰；袋内气体体积分数均于15d后达到平衡，3种包装处理中PE50自发气调能力最强，达到了4．5％～5．0％．3％～5．7％CO2。贮藏60d后，3种包装果实青皮和核仁含水量下降率均显著低于对照（P〈0．05）；鲜果腐烂指数、核仁酸价和过氧化值均显著低于对照，并表现为PE50〈thk．PE〈PE30；核仁游离脂肪酸含量为PE50〉PE30〉thk．PE。得出结论：PE50包装较thk．PE更加有效地控制了核桃青果的腐烂，并保持了较高的核仁品质与营养。The effect of modified atmosphere packaging （MAP） with three different thicknesses of PE films, PE30 （30 μm）, thk-PE （45 gin） and PE50 （50 μm）, or mulch plastic film （6 μm） as control was examined on the postharvest physiology and preservation of green walnut fruit （cultivar Xifu No. 2） during storage at 0-1 ℃. Gas concentrations in the sealed bags and respiration rate, ethylene production rate and decay index of the fruit were measured at regular intervals. Acid value, peroxide value and free fatty acid content of the kernel as well as water content of the peel and kernel were also determined after 0 and 60 days of storage. Results showed that all three PE films delayed the first respiratory peak and restrained the second one as well as ethylene production peak, and gas concentrations in all the bags reached equilibrium after 15 days. Among them, PE50 had the strongest capability of automatic atmospheric modification, providing 4.5%-5.0% 02 and 5.3%-5.7% CO2. After 60 days of storage, the peel and kernel of walnuts packaged with the three PE bags showed a significantly lower water content than those packaged with the control film （P 〈 0.05）, in addition to a significant decrease in decay index as well as kernel acid value and peroxide, with the increasing order for all these indicators： PE50 thk-PE PE30. However, kernel free fatty acid contents followed the decreasing order： PE50 〉 thk-PE 〉 PE30. From this study, it is concluded that PE50 is more effective at delaying the decay of MAP packaged green walnut fruit than thk-PE and preserving the quality and nutrients of walnut kernel.

关 键 词：核桃青果 薄膜包装贮藏 采后生理 品质 

分 类 号：S609.3[农业科学—园艺学]