GC/MS分析俄罗斯鲟鱼不同部位脂肪酸组成

通过Folch法提取俄罗斯鲟鱼不同部位总脂,采用GC/MS法对其脂肪酸组成进行分析。通过质谱数据库检索和标准品对照鉴定脂肪酸组成。研究表明,鱼肉、鱼卵、鱼皮、鱼腹中脂肪酸种类及含量类似,多不饱和脂肪酸含量均大于40%,其次为单不饱和脂肪酸(30%左右)和饱和脂肪酸(17%左右),多不饱和脂肪酸以9,12-十八碳二烯酸和DHA为主。鱼肉中总脂含量12.83%,其中,多不饱和脂肪酸为42.37%,EPA+DHA为17.25%;鱼卵总脂含量为14.46%,其中n-3脂肪酸为22.10%;鱼皮含有较高含量的n-6脂肪酸(19.43%);鱼腹总脂含量14.45%,含有较高含量的多不饱和脂肪酸(42.66%)和单不饱和脂肪酸(34.07%),EPA+DHA为17.38%;鱼鳔中未检测到n-3和n-6脂肪酸;鱼肝总脂含量为55.92%,单不饱和脂肪酸含量尤为突出,高达55.81%,以9-十八碳烯酸(49.82%)为主,饱和脂肪酸含量仅为17.24%;椎骨中总脂仅为0.09%。     

气相色谱-质谱法测定食用植物油中的脂肪酸

采用气相色谱-质谱联用仪对常用5种食用植物油的脂肪酸进行了分析,共鉴定出8种脂肪酸。其主要成分为棕榈酸、亚油酸、油酸、硬脂酸、花生酸等;不同种类的食用油脂中饱和、单不饱和、多不饱和脂肪酸比例差异较大,并且以α-亚麻酸为代表的ω-3多不饱和脂肪酸在常见食用油中含量偏低,在被测的5种常用油中,仅在大豆油中检出1.04%,坚果调和油中检出0.71%,其余3种油中未检出。     

黄颡鱼和大鳍(鳢)肌肉及鱼卵中脂肪酸组成的比较

采用GC测定了黄颡鱼和大鳍(镬)的脂肪酸组成.结果表明:在两种鱼的肌肉和鱼卵中含有22种脂肪酸.在黄颡鱼肌肉中饱和脂肪酸占34.90%;不饱和脂肪酸中,单不饱和脂肪酸占51.37%,多不饱和脂肪酸占13.74%.在黄颡鱼卵中,饱和脂肪酸占26.76%,单不饱和脂肪酸占49.51%,多不饱和脂肪酸占23.73%.从大鳍(镬)来看,肌肉中饱和脂肪酸占26.97%,单不饱和脂肪酸占48.8l%,多不饱和脂肪酸占24.23%;鱼卵中饱和脂肪酸占30.75%,单不饱和脂肪酸占44.08%,多不饱和脂肪酸占25.17%.研究揭示了黄颡鱼和大鳍(镬)的肌肉脂质中以不饱和脂肪酸为主,是理想的食品.两种鱼的鱼卵还含有较高的花生四烯酸(C20:4n-6,ARA)、廿碳五烯酸(C20:5n-3,EPA)和廿二碳六烯酸(C22:6n-3,DHA)的比例,鱼卵的食用、加工值得进一步研究和开发.     

草鱼脆化过程中腹内脂肪酸组成变化

以不同脆化期的草鱼腹内脂肪为原料,采用气相-色谱质谱(GC-MS)联用技术,研究草鱼脆化过程中腹内脂肪酸组成变化。结果显示,不同脆化期的草鱼腹内脂肪中共检出19种脂肪酸,其中饱和脂肪酸(saturated fatty acid,SFA)7种,单不饱和脂肪酸(monounsaturated fatty acid,MUFA)2种,多不饱和脂肪酸(polyunsaturated fatty acid,PUFA)10种。随着脆化时间的延长,MUFA含量显著增加,PUFA、n-6 PUFA含量显著减少(p0.05)。整个脆化过程中,SFA∶MUFA∶PUFA的比值近似于1∶2∶1,以普通草鱼最为接近。而n-3 PUFA在脆化20 d时开始减少(p0.05),始终低于普通草鱼。n-6/n-3 PUFA的比值为3.36%±0.04%~4.10%±0.04%,脆化20 d时最高。研究表明,虽然脆化改变了腹内脂肪酸的组成,但脆肉鲩腹内脂肪仍具有较好的开发价值。     

功能性n-3多不饱和脂肪酸的研究进展

脂肪酸是生命代谢活动中一种重要化合物，根据脂肪酸碳链数上的双键数将脂肪酸分为饱和脂肪酸、单不饱和脂肪酸、多不饱和脂肪酸三类。文章对n-3多不饱和脂肪酸来源、合成过程、n-3和n-6多不饱和脂肪酸的结构差异以及生物活性进行综述，为n-3多不饱和脂肪酸在功能保健食品、医学药用领域及基础研究进一步探索与全面开发提供理论依据。     

小品种食用油的脂肪酸营养功能

分析论述了ω-3系列多不饱和脂肪酸(ω-3PUFA)、ω-6系列多不饱和脂肪酸(ω-6 PUFA)、单不饱和脂肪酸(MUPA)的特殊营养功效,阐述了不同类型的小品种食用油的脂肪酸营养特征。     

青海高原牦牛肉宰后成熟过程中脂肪酸组成及含量变化分析

为研究青海高原牦牛肉宰后成熟过程中不同部位肉脂肪酸组成和含量变化及差异,本实验选取青海高原牦牛冈上肌、背最长肌和半腱肌3个部位肉,利用气相色谱-质谱法(GC-MS)检测3个部位肉宰后成熟0、1、2、3、5、7和14 d的脂肪酸组成及含量。结果发现,3个部位肉中均检测出22种脂肪酸,其中,饱和脂肪酸8种,单不饱和脂肪酸5种,多不饱和脂肪酸9种,且均随宰后成熟时间的延长呈先增加后降低的趋势。3个部位肉宰后成熟过程中的脂肪酸组成相同但含量有差异,n-6/n-3比值均在1.0~3.0之间,脂肪酸组成比例较好。通过对青海高原牦牛3个不同部位肉不同成熟时间的脂肪酸组成及含量进行主成分分析,发现3个部位0、1和2 d具有相似性,主要有n-6系和n-3系多不饱和脂肪酸亚油酸(C18:2n6c)、花生四烯酸(C20:4n6)、顺-8,11,14-二十烷三烯酸(C20:3n6)、二十二碳六烯酸(C22:6n3)和单不饱和脂肪酸反油酸;3、5和7 d具有相似性,此期间大多数饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸含量增加;14 d则不同于其他时间,主要是此期间产生了大量的γ-亚麻酸(C18:3n6)。     

澳洲美利奴羊肉脂肪酸组成

选择3 只澳洲美利奴羔羊的背最长肌、臀肌及臂三头肌,利用气相色谱-质谱联用技术对其脂肪酸含量进行测定及分类探讨。结果表明：澳洲美利奴羊肉中共含有脂肪酸35 种,其中C15:1、C16:0、C17:1、C18:0、C18:1 n-9c脂肪酸含量较高,3 个部位肌肉中：不饱和脂肪酸含量＞饱和脂肪酸含量＞单不饱和脂肪酸含量＞多不饱和脂肪酸含量,且每个部位肌肉中单不饱和脂肪酸含量比多不饱和脂肪酸含量均高出2～3 倍;n-3脂肪酸亚麻酸甲酯（C18:3 n-3）在臂三头肌中的含量显著高于背最长肌（P＜0.05）;与另外2 个部位相比,臂三头肌总脂肪酸、饱和脂肪酸、不饱和脂肪酸、中链脂肪酸及长链脂肪酸含量均最高;臂三头肌中多不饱和脂肪酸与饱和脂肪酸含量比值最高,背最长肌中最低。     

鱼油n-3多不饱和脂肪酸的代谢与抗血栓、抗炎症的机制

鱼油中富含n-3多不饱和脂肪酸,特别是廿碳五烯酸和廿二碳六烯酸.在营养学和医药学的各个领域中日益被重视.随着生化和生理研究的进展,n-3脂肪酸的代谢与对人前列腺素、白三烯组成的影响已被基本阐明,并被用于抗血栓、抗炎症的研究.本文讨论了n-3脂肪酸对人前列腺、白二烯的调节作用及作为疗效食品的机制.     

小尾寒羊不同部位挥发性风味物质和脂肪酸分析

为了研究小尾寒羊不同部位挥发性风味物质和脂肪酸组成的差异,并初步评价4个部位脂肪酸的营养价值。对4月龄小尾寒羊后腿、里脊、上脑和羊排4个部位的脂肪含量、蛋白质含量、挥发性风味物质和脂肪酸组成进行了对比分析。结果表明:小尾寒羊主要风味化合物为辛醛、壬醛、辛醇、1-辛烯-3-醇、辛酸和癸酸。里脊部位所含醛类、醇类和酯类化合物种类及相对含量均较高,对羊肉风味形成起主要作用。上脑部位的不饱和脂肪酸/饱和脂肪酸比值显著高于其他部位,多不饱和脂肪酸/饱和脂肪酸比值大于0.4,单不饱和脂肪酸和多不饱和脂肪酸的含量均较高。因而上脑部位的脂肪酸组成更符合人体对脂肪酸营养价值的需求。     

Omega-3 Fatty Acids in Lake Superior Fish

Proximate analysis and fatty acid composition of eight commercially important species of Lake Superior fish were determined. Palmitic acid (C16:0) was the predominant saturated fatty acid, accounting for 68–79% of total saturated acids. Oleic acid (C18:1) was the most abundant monounsaturated fatty acid. Linoleic acid (C18:2), linolenic acid (C18:3), eicosapentaenoic acid (C20:5) and docosahexaenoic acid (C22:6) were the predominant polyunsaturated fatty acids. Brining, smoking and refrigerated storage caused a reduction in total lipid, but only a small loss in n-3 fatty acids. The data revealed that most Lake Superior fish examined were excellent sources of polyunsaturated fatty acids with very high levels of omega-3 (n-3) fatty acids, especially eicosapentaenoic and docosahexaenoic acids.     

海水养殖花鲈和淡水养殖花鲈肌肉脂肪酸组成和含量分析

采用Folch 液回流提取投喂相同配合饲料的海水养殖花鲈和淡水养殖花鲈背部肌肉脂质,脂质经氢氧化钾-三氟化硼法甲酯化后进行气相色谱分析。结果表明：海水养殖花鲈和淡水养殖花鲈肌肉脂肪酸组成存在一定差异。海水花鲈肌肉脂肪酸中单不饱和脂肪酸(MUFA)、n-3 系列多不饱和脂肪酸(PUFA)、EPA(C20:5 n-3)和DHA(C22:6 n-3)含量明显高于淡水花鲈,而饱和脂肪酸(SFA)、n-6 系列PUFA 和AA(C20:4 n-6)含量则低于淡水养殖花鲈。海水养殖花鲈和淡水养殖花鲈肌肉中n-6 和n-3 系列PUFA 比值分别为0.27 和0.42,均远低于HMSO(英国卫生部)推荐的最高安全限值(4.0)。     

Nutraceutical functions of sesame: a review

The results of recent food chemical and nutraceutical studies on the traditionally well-known health value of sesame are described, including some aspects of the utilization of sesame. The highly antioxidative activity of sesame oil was clarified and found to involve newly discovered lignans. The antiaging effect of sesame was elucidated to be due to the strong vitamin E activity caused by a novel synergistic effect of sesame lignans with tocopherols resulting from the inhibition of metabolic decomposition of tocopherols by sesame lignans. The specific inhibitory action of sesame lignans on Delta5 desaturase in polyunsaturated fatty acid synthesis was found in studies on the microbial production of polyunsaturated fatty acids. This effect of sesame lignans was extended to various effects on fatty acid metabolism involving lowering fatty acid concentration in liver and serum due to acceleration of fatty acid oxidation and suppression of fatty acid synthesis, and the controlling influence on the ratio of n-6/n-3 polyunsaturated fatty acids under excess intake of either n-6 or n-3 fatty acids in the diet. Sesame lignans lowered the cholesterol concentration in serum, especially in combination with tocopherol, due to the inhibition of absorption from the intestine and suppression of synthesis in the liver. Sesame lignans also showed other useful functions such as acceleration of alcohol decomposition in the liver, antihypertensive activity, immunoregulatory activities, anticarcinogenic activity, and others.     

Polyunsaturated Fatty Acids and Fat in Fish Flesh for Selecting Species for Health Benefits

An awareness of the protective roll of n-3 polyunsaturated fatty acids against development of cardiovascular disease has prompted the promotion of fish consumption. It is assumed that those fish rich in polyunsaturated fat and particularly those having high ratios of n-3 to n-6 polyunsaturated fatty acids would confer the most benefit. The total fat and fatty acid compositional data are reported herein for 41 different species of fish that are mostly found in the coastal waters of the Eastern United States.     

Fatty acid composition in ocean-ranched Atlantic salmon (Salmo salar)

Summary  The difference in fat content and fatty acid composition in the muscle of one-and two-year-old ocean-ranched Atlantic salmon ( Salmo salar ) was studied and compared using spot samples. The fat content in the muscle of 1-year-old salmon was 4.8% of wet weight, and 5.0% in 2-year-old salmon. The effect was not statistically significant. The main constituents of the fat were palmitic acid (16:0), oleic acid (18:1,n-9), gadoleic acid (20:1,n-9) and erucic acid (22:1,n-9). Eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) were predominant among the polyunsaturated fatty acids (PUFAs). There was a significant difference between the groups in relation to the content of stearic acid (18:0), palmitoleic acid (16:1,n-9) and oleic acid (18:1,n-9).     

大足黑山羊不同部位肌肉脂肪酸比较研究

为研究大足黑山羊不同部位肌内脂肪、脂肪酸含量和组成方面的差异,以处于相同饲喂条件且体质量相近的6 只5 月龄大足黑山羊为研究对象,分别利用索式抽提法和气相色谱-质谱联用法测定背最长肌和臂三头肌肌内脂肪含量和脂肪酸组成。结果表明：大足黑山羊背最长肌中肌内脂肪含量为3.2%,臂三头肌为3.0%,背最长肌略高于臂三头肌;大足黑山羊背最长肌和臂三头肌各检测出33 种脂肪酸,2 个部位各脂肪酸含量基本一致,但与背最长肌相比,臂三头肌反油酸（C18:1 n-9t）含量较高,而介子酸（C22:1）含量较低;16 种饱和脂肪酸中,仅十七碳酸（C17:0）含量背最长肌极显著高于臂三头肌（P＜0.01）;17 种不饱和脂肪酸中,4 种脂肪酸在不同部位间存在显著差异,背最长肌二十碳烯酸（C20:1）含量极显著高于臂三头肌（P＜0.01）,油酸（C18:1 n-9c）含量显著高于臂三头肌（P＜0.05）,臂三头肌反油酸（C18:1 n-9t）含量极显著高于背最长肌（P＜0.01）;臂三头肌和背最长肌中不同种类脂肪酸相对含量：单不饱和脂肪酸＞饱和脂肪酸＞多不饱和脂肪酸＞中链脂肪酸,臂三头肌和背最长肌中饱和脂肪酸和单不饱和脂肪酸相对含量之和分别为88.4%和86.3%;臂三头肌和背最长肌中n-3/n-6值相近且均在3.0左右;背最长肌多不饱和脂肪酸与饱和脂肪酸含量比值（P/S）为0.45,臂三头肌P/S值为0.41,背最长肌高于臂三头肌。说明不同部位大足黑山羊肉脂肪酸含量及组成存在差异,并可能在一定程度上影响肉的风味及营养价值。     

膳食中多不饱和脂肪酸营养与生理功能的研究进展

概述了多不饱和脂肪酸的种类、来源、营养和生理功能的相关研究，包括n-6系列多不饱和脂肪酸、n-3系列多不饱和脂肪酸。阐述了膳食合理比例的n-6/n-3多不饱和脂肪酸是保持身体健康的关键。     

脂肪酸营养与功能的最新研究

概述了脂肪酸的种类以及与胆固醇和动脉硬化的相关研究,同时综述了各类脂肪酸营养与功能的最新研究,包括有n-6系多价不饱和脂肪酸、n-3系多不饱和脂肪酸、饱和脂肪酸、一价不饱和脂肪酸,以及一些微量脂肪酸如共轭脂肪酸、中短边脂肪酸等等。     

Effect of a linseed diet on lipid oxidation, fatty acid composition of muscle, perirenal fat, and raw and cooked rabbit meat

Forty Californian×New Zealand rabbits (1kg initial body weight) were fed a control or a linseed isoenergetic diet containing 30g of extruded linseed/kg. Twenty rabbits for each dietary treatment were slaughtered at 11 weeks of age, at 35 days after the start of the experiment. Feeding the linseed diet increased (P<0.005) the content of 18:2n-3 in muscles, perirenal fat, and raw and cooked meat. The long chain n-3 polyunsaturated fatty acid (PUFA) contents were also increased (P<0.01) in the meat. The linseed diet produced a robust decrease in the n-6/n-3 ratio. Cooking did not alter n-3 PUFA more than saturated fatty acids (SFA) or monounsaturated fatty acids (MUFA). However, n-6 PUFA were altered by cooking. The oxidative stability of Longissimus dorsi was not affected by the linseed diet, even after 300min of forced-oxidation. Inclusion of linseed in rabbit diets is a valid method of improving the nutritional value of rabbit meat.     

青海牦牛肉与秦川牛肉氨基酸和脂肪酸的比较研究

通过青海牦牛肉与秦川牛肉的氨基酸和脂肪酸的比较研究,分析青海牦牛肉品质的特性及其潜在优势.选取秦川牛肉,青南、大通和环青海湖地区的成年牦牛肉以及大通犊牦牛肉进行氨基酸和脂肪酸的相关研究.结果表明:牦牛肉各组的蛋白质含量高于秦川牛肉,但差异不显著(P＞0.05);脂肪含量都低于秦川牛肉,差异极显著(P＜0.01).青南地区成年牦牛肉的必需氨基酸/非必需氨基酸(EAA/NAA)值、必需氨基酸/氨基酸总量(EAA/TAA)值、18∶2cis-12,15、α-亚麻酸、20∶0、多不饱和脂肪酸(PUFA)、必需脂肪酸(EFA)、多不饱和脂肪酸/脂肪酸总量(P∶S)值和n-3多不饱和脂肪酸都显著高于秦川牛肉(P＜0.05或P＜0.01);16∶0、二十碳五烯酸(EPA)和n-6/n-3值都显著低于秦川牛肉(P＜0.05或P＜0.01).大通成年牦牛肉的赖氨酸、组氨酸和15∶0都显著高于秦川牛肉(P＜0.05或P＜0.01);月桂酸、亚油酸、PUFA、EFA、n-6多不饱和脂肪酸和n-6/n-3值都显著低于秦川牛肉(P＜0.05或P＜0.01).环湖地区成年牦牛肉的脯氨酸、15∶0、16∶1cis-9、17∶0和18∶2cis-12,15都显著高于秦川牛肉(P＜0.05或P＜0.01);月桂酸和n-6/n-3值都显著低于秦川牛肉(P＜0.05或P＜0.01).大通犊牦牛肉的色氨酸、肉豆蔻酸、17∶1cis-9、18∶1cis-11、亚油酸、α-亚麻酸、20∶3cis-5,8,11、20∶3cis-7,10,13、花生四烯酸(AA)、EPA、PUFA、EFA、P∶S值、n-3多不饱和脂肪酸和n-6多不饱和脂肪酸都显著高于秦川牛肉(P＜0.05或P＜0.01);脯氨酸、14∶1cis-9、棕榈酸、17∶0、油酸、SFA、MUFA和n-6/n-3值都显著低于秦川牛肉(P＜0.05或P＜0.01).结论:青海成年牦牛肉的蛋白质和必需氨基酸含量稍高于秦川牛肉,组成与秦川牛相近,但犊牦牛肉的氨基酸含量稍差一些.牦牛肉的n-6/n-3多不饱和脂肪酸比秦川牛肉合理,都在4.0左右,其中犊牦牛肉的P∶S值为1.15,说明牦牛肉的脂肪酸品质优,尤其是犊牦牛肉.