不同预冷方式对去皮莴苣预冷效果及贮运品质的影响  

Effect of different precooling methods on precooling and quality of peeled lettuce during storage and transportation

作　　者：尚海涛 陈亦辉[2] 凌建刚 朱麟 康孟利 俞静芬 林旭东 

机构地区：[1]宁波市农业科学研究院农产品加工研究所,浙江宁波315040 [2]海通食品集团余姚有限公司,浙江余姚315470

出　　处：《食品工业科技》2015年第7期328-331,335,共5页Science and Technology of Food Industry

基　　金：国家"十二五"科技支撑计划项目子课题(2012BAD38B01);国家星火计划项目子课题(2012GA701003)

摘　　要：本文以去皮莴苣为试材,对比分析了不同预冷方式预冷效果及研究了不同预冷方式处理后对贮运过程中感官品质、褐变度、叶绿素、PPO和POD活性以及MDA含量的影响。结果表明:去皮莴苣运输过程中的关键问题是褐变,未预冷贮运时间仅约12h,真空预冷和差压预冷速度虽快,但贮运过程中回温速度也较快,无法有效阻止褐变的发生;就护绿保鲜效果而言,冰冷和水冷相近,效果明显,不仅可以降低温度,还可以有效阻止去皮莴苣与空气(氧)的接触,进而阻止褐变的发生。采用此两种方式能使去皮莴苣的感官品质明显改善,褐变度显著降低,保持较高叶绿素含量,减缓PPO和POD活性及MDA含量的上升;又由于水冷易产生异味,可知冰冷优于水冷,可以延长贮运时间至24h。因此,冰冷是现阶段去皮莴苣最适的预冷贮运方法。Taking peeled lettuce as tested material, a contrastive analysis of different precooling methods was given, and the effect of different precooling methods on sensory quality, browning degree,chlorophyll content, PPO and POD activities and MDA content during storage and transport were investigated.The results showed that the key problem of peeled lettuce was browning,the storage and transport time of no precooling was only about 12h; the speeds of vacuum precooling and pressure-difference cooling were faster than other methods,while warming speeds were also faster ,the browning couldn＇t be effectively prevented ;the effect of ice and hydro cooling was similar and obvious, not only decreased the temperature, but also effectively blocked access to air （ oxygen）, thereby prevented the browning. The two methods could make the sensory quality obviously improved, the browning degree decreased significantly,the higher chlorophyll content maintained,and the rise of PPO and POD activities and MDA content slowed ;the effect of ice cooling was better than hydro cooling for the peculiar smell,the storage and transport time of ice cooling could be prolonged to 24h.Thus,the most suitable precooling method of peeled lettuce was ice cooling.

关 键 词：去皮莴苣 预冷 冰冷 贮运品质 褐变 

分 类 号：TS255.3[轻工技术与工程—农产品加工及贮藏工程]