自然光照对冷藏条件下草鱼肌肉脂肪酸组成及含量的影响  

Effect of Natural Light on Fatty Acid Composition of Grass Carp Muscle during Chilled Storage

作　　者：王建辉[1] 刘冬敏[1] 刘永乐[1] 王发祥[1] 俞健[1] 李向红[1] 杨晶[1] 

机构地区：[1]长沙理工大学化学与生物工程学院,湖南长沙410114

出　　处：《食品科学》2013年第16期336-340,共5页Food Science

基　　金：湖南省科技重大专项(2010FJ1007);"十二五"国家科技支撑计划项目(2012BAD31B08);湖南省重点学科建设项目

摘　　要：采用气相色谱-质谱联用(GC-MS)法探讨冷藏条件下(2～4℃)自然光照对草鱼肌肉各种脂肪酸相对含量变化的影响。结果表明:冷藏期间草鱼肌肉油酸、棕榈油酸等单不饱和脂肪酸(MUFA)以及亚油酸、α-亚麻酸等多不饱和脂肪酸(PUFA)不断降解,其相对含量随冷藏时间的延长显著降低(P<0.05),导致棕榈酸、硬脂酸等饱和脂肪酸(SFA)的相对含量显著增加(P<0.05)。光照对冷藏草鱼肌肉中棕榈酸、硬脂酸及SFA总量,亚油酸、α-亚麻酸及PUFA总量包括ω-3 PUFA的降解均具有显著影响(P<0.05),导致光照组棕榈酸、硬脂酸及SFA的相对含量显著高于避光组,而光照对棕榈油酸、油酸、MUFA总量及ω-6 PUFA影响不显著。PUFA较MUFA先发生氧化降解,且冷藏10d后其降解程度比MUFA高出6.30%。ω-6 PUFA降解迅速,其降解程度高于ω-3 PUFA。由此说明,脂肪酸的不饱和度越高,降解速度越快,降解程度越深。不饱和脂肪酸(UFA)的降解造成草鱼肌肉营养价值的降低,对新鲜草鱼肌肉进行避光包装后冷藏有利于减少其脂质的降解,保证肌肉较高的营养价值及加工品质,延长其货架期。Fatty acid composition in grass carp muscle and their content changes during chilled storage were studied using gas chromatography-mass spectrometry（GC-MS） to explore the effect of natural light on the amount and composition of fatty acids in grass carp muscle.The results obtained showed that monounsaturated fatty acids（MUFA） such as 9-octadecenoic acid and 9-hexadecenoic acid as well as polyunsaturated fatty acids（PUFA） such as 9,12-octadecadienoic acid and 9,12,15-octadecatrienoic acid were continuously degraded during chilled storage.Their relative contents significantly declined（P 0.05） with prolonged storage time,resulting in a significant increase in the relative content of saturated fatty acids（SFA） such as hexadecanoic acid and octadecanoic acid（P 0.05）.Light had significant effects on the degradation of 9,12-octadecadienoic acid,9,12,15-octadecatrienoic acid and the content of total PUFAs including ω-3 PUFAs（P 0.05）,resulting in significantly higher relative contents of hexadecanoic acid,octadecanoic acid and total SFAs in the light group than in the dark group.However,the contents of 9-octadecenoic acid,9-hexadecenoic acid,total MUFAs and ω-6 PUFAs were not significantly affected by light.PUFAs were oxidatively degraded earlier and the extent of degradation was 6.30% higher than that of MUFAs after 10 d of chilled storage.ω-6 PUFAs were degraded fast and its degradation extent was higher than that of ω-3 PUFA.Accordingly,the greater the degree of unsaturation of fatty acids,the faster the degradation rate,and the greater the extent of degradation.The degradation of unsaturated fatty acids deteriorates the nutritional value of grass carp muscle.Chilled storage in the dark is helpful to prevent lipid oxidation and thus ensure the nutritional value and processing quality and prolong the shelf life.

关 键 词：草鱼 脂肪酸 光照 气相色谱-质谱联用 

分 类 号：TS201.6[轻工技术与工程—食品科学] TS207.4[轻工技术与工程—食品科学与工程]