鄱阳湖10种淡水鱼脂肪酸的特性研究

为了探讨中国最大淡水湖鱼类脂肪酸的特点,采用气相色谱法对鄱阳湖10种野生淡水鱼类脂肪酸的组成和含量进行分析。结果发现,鄱阳湖10种淡水鱼中最丰富的脂肪酸是油酸(C18∶1n9);鱼中多不饱和脂肪酸(PUFA)的含量随鱼类品种的不同有较大的差别,大眼鳜肌肉的二十二碳六烯酸(DHA)含量最高达14.19%;赤眼鳟的花生四烯酸(AA)含量最高,肌肉和鱼头分别达13.53%和12.07%;麦穗鱼的二十碳五烯酸(EPA)含量最高,肌肉和鱼头分别为7.60%和7.92%。所分析的鱼PUFA/饱和脂肪酸(SFA)的值都在0.5以上,n6PUFA/n3PUFA为0.45～1.19;此外,鱼中还含有一定量的奇数碳脂肪酸,银鲴鱼头中含量最高达6.84%。结果表明鄱阳湖水域中,鱼PUFA有明显的特征,部分鱼中DHA和EPA的含量显著高于一般的淡水鱼,甚至与海鱼相近。PUFA和n3PUFA含量与鱼的生活习性有较大关系,以藻类为主食的鱼>以鱼虾为主食的鱼>以软体动物和水生昆虫为主食的鱼。      

鄱阳湖野生鱼类脂肪酸含量的比较研究

通过研究鄱阳湖野生淡水鱼类脂肪酸的含量,了解鄱阳湖鱼类中饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸(PUFA)的含量和构成比。鱼肌肉用氯仿甲醇溶液提取脂肪,碱法甲酯化后用气相色谱分析。结果显示:鱼肌肉中的PUFA的含量随鱼类品种的不同有较大的差别,范围为18.65%～43.07%;二十二碳六烯酸(DHA)和二十碳五烯酸(EPA)的含量也变化较大,其中黄颡鱼的DHA含量最高,可达10.72%,而鲹鲦的EPA含量则是所测鱼类中最高的,达4.61%。其中n-3系不饱和脂肪酸与n-6系不饱和脂肪酸的比例也相差悬殊,从1:0.7到1:2.5不等。不同科目的鱼,在C22:4n-6、C22:5n-3(DPA)含量上有显著性差异。不同生活习性的鱼,其共轭亚油酸(CLA)、C20:4n-6、C22:2n-6、C22:4n-6、C22:5n-3、C22:6n-3(DHA)均存在显著性差异。研究结果表明鄱阳湖水域中,鱼肌肉的多不饱和脂肪酸与鱼的生活习性如生活在不同的水层和食性等有较大关系,鱼的遗传因素与脂肪酸比例和含量也有一定关系。     

3种淡水鱼油脂肪酸的含量分析

运用气相色谱质谱联用方法,分析了鲢鱼、罗非鱼和草鱼3种淡水鱼脂肪的脂肪酸组成。淡水鱼脂肪经氯仿/甲醇(体积比=2∶1)提取后,用三氟化硼甲醇溶液衍生,衍生物用气相色谱质谱法分析。结果显示,3种淡水鱼脂肪多不饱和脂脂酸(PUFA)含量为29.26%～41.49%,主要有亚油酸(C18∶2)、亚麻酸(C18∶3)、花生四烯酸(C20∶4)、二十二碳五烯酸(C20∶5,EPA)和二十二碳六烯酸(C22∶6,DHA);单不饱和脂肪酸(MUFA)的含量为26.46%～39.60%,主要有棕榈油酸(C16∶1)和油酸(C18∶1);饱和脂肪酸(SFA)的含量为23.35%～37.05%,主要有肉豆蔻酸(C14∶0)、棕榈酸(C16∶0)和硬脂酸(C18∶0)。3种淡水鱼脂肪SFA∶MUFA∶PUFA的比值,鲢鱼为0.56∶0.84∶1;罗非鱼为1.07∶1.35∶1;草鱼为1.02∶0.72∶1。鲢鱼、罗非鱼和草鱼脂肪的n-6/n-3脂肪酸比值分别为1.16,2.46和1.98。3种淡水鱼脂肪具有较高的营养和开发价值。     

15种淡水鱼肌肉脂肪含量及脂肪酸组成分析

为比较淡水鱼肌肉脂肪酸在鱼类科、目以及种属间的差异,本文采用氯仿-甲醇(体积比=2:1)法提取15种淡水鱼背部肌肉的粗脂肪,运用气相色谱-质谱联用方法,分析了15种淡水鱼脂肪酸的组成。结果表明,15种淡水鱼肌肉粗脂肪含量在3.76%~14.74%,15种淡水鱼共检出24种脂肪酸,其中8种饱和脂肪酸(SFA),5种单不饱和脂肪酸(MUFA)和11种多不饱和脂肪酸(PUFA)。不同淡水鱼脂肪酸除个别有差异外,其他组成基本相同,但其含量因淡水鱼所在目、科和种属不同存在显著性差异,多不饱和脂肪酸含量最高,均在35%以上。不同鱼种的粗脂肪中EPA和DHA总含量有所差异,鲈鱼粗脂肪中DHA和EPA最高,总含量达到30%,而泥鳅粗脂肪中的EPA和DHA总含量仅为8.51%。部分鱼种可以作为EPA和DHA的良好膳食来源,具有较高的利用和开发价值。     

洞庭湖水域淡水鱼类脂肪酸含量研究

目的分析洞庭湖水域出产的常见可食用淡水鱼多种主要脂肪酸的含量。方法于洞庭湖水域采集当地常见可食用淡水鱼(每种3~4份样品),提取总脂后以气相色谱法分析其各种脂肪酸含量。结果共采集12种淡水鱼类,其总脂含量占可食部范围为1.14%(鳙鱼)~7.55%(黄颡鱼),绝大多数鱼种含量最多的饱和脂肪酸、单不饱和脂肪酸、n-6和n-3多不饱和脂肪酸分别为棕榈酸、油酸、亚油酸和二十二碳六烯酸(DHA)。DHA含量(mg/100 g可食部)均值范围为19.7(鳝鱼)~358.4(长吻鮠)。二十碳五烯酸(EPA)(r=0.523,P0.000 1)、二十二碳五烯酸(r=0.462,P=0.000 3)和DHA(r=0.576,P0.000 1)含量分别与总脂含量相关。结论洞庭湖水域常见淡水鱼脂含量及脂肪酸含量具有明显种属差异性,部分鱼种可以作为EPA和DHA的良好膳食来源而被推荐。     

5种经济鱼类内脏脂肪酸含量及组成分析

为探明经济鱼类内脏利用价值,采用水解法提取5种经济鱼类内脏脂肪酸,应用气相色谱外标法分析脂肪酸含量及组成.结果表明,5种经济鱼类共检出30种脂肪酸,其中11种饱和脂肪酸,8种单不饱和脂肪酸和11种多不饱和脂肪酸.秋刀鱼总脂肪酸含量最高,为(2504.27±64.99)mg/100 g,鳙鱼内脏最低,为(712.28±5...     

四种淡水鱼致敏蛋白免疫原性研究

对常见的食物过敏原,草鱼（Ctenopharyngodon idellus）、乌鳢（Ophicephalus argus）、鲇鱼（Silurus asotus）、花鲈（Lateolabrax japonicus）四种淡水鱼进行了特异性抗原的识别,通过coca’s缓冲液分别于四类鱼肌肉组织中提取蛋白粗提液,经SDS-PAGE分离出多种分子量不同的蛋白组分并对其进行分析,再通过Western-blotting识别四种淡水鱼过敏原研究其免疫原性。由SDS-PAGE电泳分别得到四种淡水鱼全蛋白电泳图,通过免疫印迹等方法发现草鱼与IgE结合的阳性带主要有4条（107、62、50、27ku）,乌鳢与IgE结合的阳性带主要有6条（62、50、34、32、28、17ku）,鲇鱼与IgE结合的阳性带主要有4条（62、50、39、37ku）,花鲈与IgE结合的阳性带主要有6条（62、50、37、34、32、18ku）。     

淡水鱼加工技术研究

在分析淡水鱼加工特性的基础上,开发出鱼糜制品和熏烤制品两类鱼产品,并对其工艺过程、加工条件进行了较为深入的技术研究.     

华东地区10种油炸方便面脂肪酸组成分析

对华东地区市售的１０种油炸方便面的脂肪酸组成进行了气相色谱（ＧＣ）分析。结果表明，它们的主要脂肪酸组成为豆蔻酸、棕榈酸、硬脂酸、油酸、亚油酸，其中以棕榈酸、油酸一较高，缺少高度不饱和脂肪酸，尤其是亚麻酸。建议在生产油炸方面时应充分考虑油脂营养的强化因素。     

Stability of potassium iodide and omega-3 fatty acids in fortified freshwater fish emulsion sausage

Oxidative stability of emulsion sausages prepared from African walking catfish (AF: Clarias gariepinus) and rohu (RH: Labeo rohita) fortified with three levels of the refined tuna oil (2%, 6%, and 10%) with 150 μg KI/100 g sample and without KI was investigated. The control was prepared using 20% soybean oil and without KI. Samples were vacuum-packed and stored at 4 °C. Iodine content decreased approximately 14% after cooking and remained constant throughout storage. Sausages fortified with tuna oil showed higher level of n-3 (eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)), but lower level of n-6 fatty acids (P<0.05) than the control. The ratio of n-6 to n-3 fatty acids of all samples decreased with an increase of tuna oil addition and was stable throughout 4 weeks of storage. Degradation of linoleic (LA) and linolenic acid (LNA) mainly occurred in the samples added 2% tuna oil whereas samples fortified with higher tuna oil (6-10%) exhibited higher loss of EPA and DHA. Hydroperoxide (HPV) and thiobarbituric reactive substances (TBARS) values were increased as addition level of tuna oil increased. Textural properties were not affected during storage at 4 °C for up to 4 weeks (P<0.05). Based on lipid stability results, 2% fortification of the refined tuna oil was recommended for emulsion sausage prepared from both species. Addition of 150 μg KI/100 g had no effect on lipid oxidation of fish sausages (P<0.05).     

Characterisation of furan fatty acids in Adriatic fish

Furan fatty acids (F-acids) were characterised in the fillet of European hake (Merluccius merluccius), horse mackerel (Trachurus trachurus), common sole (Solea solea), European anchovy (Engralius encrasicolus), Atlantic mackerel (Scomber scombrus), European pilchard (Sardina pilchardus) was harvested in Adriatic Sea during the spring and the summer. The main F-acids were of the saturated series: 12,15-epoxy-13-methyleicosa-12,14-dienoic acid [MonoMe(11,5)] in European hake and 12,15-epoxy-13,14-dimethyleicosa-12,14-dienoic acid [DiMe(11,5)] in all the other fish species; 12,15-epoxy-13,14-dimethyloctadeca-12,14-dienoic acid, 10,13-epoxy-11-methyloctadeca-10,12-dienoic acid and 14,17-epoxy-15,16-dimethyldocosa-14,16-dienoic acid were present in all fish species in trace amounts. Other identified F-acids were the olefinic congeners 12,15-epoxy-13,14-dimethyleicosa-12,15,16-trienoic acid and 12,15-epoxy-13,14-dimethyleicosa-10,12,14-trienoic acid. European pilchard had the highest F-acids content (30 mg/100 g fillet), whereas horse mackerel showed the lowest content (less than 0.1 mg/100 g fillet). Eicosapentaenoic acid (EPA) was positively correlated with MonoMe(11,5) and DiMe(11,5), showing that the biosynthesis of docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) is presumably competitive with that of F-acids.     

烹饪时间对鱼肉中脂肪酸的影响

目的 考察不同烹饪时间对鱼肉中脂肪酸营养价值的影响, 并对不同鱼类的适宜烹调时间进行评价。方法 采用清蒸的方式对秋刀鱼、石斑鱼、鲫鱼和罗非鱼进行烹调, 利用氯仿-甲醇提取法提取鱼肉脂肪酸, 通过气相色谱技术(gas chromatography, GC)对鱼肉中脂肪酸进行定性定量, 讨论烹饪时间对不同鱼肉中脂肪酸含量变化的影响。结果 随着烹饪时间的增加, 4种不同种类的鱼肉中不饱和脂肪酸的含量都呈现下降趋势, 当烹饪时间为0.5~1.0 h时, 不饱和脂肪酸二十碳五烯酸(eicosapentaenoic acid, EPA)、二十二碳六烯酸(docosahexaenoic acid, DHA)、油酸、亚油酸、亚麻酸含量下降速率最快并且产生有害脂肪酸(反式脂肪酸), ω-6/ω-3脂肪酸比值也呈现出上升趋势, 鱼肉脂肪酸营养价值降低。结论 在对鱼肉进行烹饪时, 应严格控制鱼肉烹饪时间在0.5 h左右, 才能有效的保证鱼肉中脂肪酸的营养价值。     

Chemical compositions and fatty acid profiles of three freshwater fish species

This study investigated the chemical composition and fatty acid profiles of Cyprinus(C) carpio, Labeo(L) rohita and Oreochromis(O) mossambicus from the Indus River, Pakistan. Significant differences were observed for most chemical components and fatty acids (P < 0.01) in the examined fish species. O. mossambicus,C. carpio and L. rohita were high in saturated, mono-unsaturated and poly-unsaturated fatty acids, respectively. Palmitic acid was the most abundant fatty acid in all species ranging from 32% to 46%. Although these fish contained reasonable amounts of essential PUFA such as docosahexaenoic, eicosapentaenoic and arachidonic acids, L. rohita contained the highest amounts of PUFA and protein. These fish contained appreciable levels of Omega-6 PUFA suggesting that these fish especially L. rohita could be used as a source of healthy diet for humans. These findings may benefit the fishing industry, nutritionists and researchers who are striving to improve the nutritive value, processing and marketing of selected fish species.     

Changes of amino acid and fatty acid profile in freshwater fish after smoking

Three freshwater fishes: common carp, rainbow trout and northern pike were chosen for the evaluation of amino acid and fatty acid composition—fresh and after smoking. Smoking led to the increase in almost all amino acids, with the highest amount of EAA in common carp. This process led also to the enhancement in the level of SFA and the decrease in PUFA/SFA ratio in fishes. PI values were lower after this process for all fishes. HH ratio was also decreased (except for northern pike), while AI and TI were enhanced in all smoked samples.

Practical applications

Fish and fish products consumption (especially freshwater) is still insufficient despite their proven health‐promoting properties. Because of the susceptibility of fish to perish, their preservation becomes a necessity. Smoking is one of the oldest food processing methods in the world. It imparts a characteristic color and flavor of the product. This process influences also on chemical composition of muscle protein and fat. Thus, the aim of this study was to investigate changes in amino acids composition and fatty acids profile in common carp, rainbow trout and northern pike, as a result of smoking. It is very important to increase consumer knowledge concerned on the species being the most suitable for traditional preservation method, taking into consideration the retaining of beneficial fish compounds.     

n-3 polyunsaturated fish fatty acids in a fish-oil-supplemented bread

White bread enriched in n-3 fatty acids in the form of gelatine-coated fish oil and marketed in Denmark since 1990 under the name of ‘Omega Bread’, was found to be a reliable and significant source of higher n-3 polyunsaturated fatty acids (with 20 and 22 C atoms). The bread from six bakeries contained 40-55 mg per 100 g more n-3 fatty acids. By eating 200 g daily of this bread one gets some 25-30% of the amount of higher n-3 polyunsaturated fatty acids present in 30 g of mixed fish. The daily ingestion of this amount of fish over a period of 20 years is known to reduce mortality from coronary heart disease by more than 50%. The supplement of n-3 polyunsaturated fatty acids obtained by eating Omega Bread daily in place of other types of white bread is expected to reduce coronary heart disease. In addition, such an increased daily ingestion of n-3 polyunsaturated fatty acids over a long-term period may possibly have other beneficial health effects. It is recommended that the intake of higher n-3 fatty acids in industrialised Western societies should be increased by more than can be obtained by a daily ration of Omega Bread. It is therefore advisable that consumption of Omega Bread is combined with an increased intake of fish and/or fish oil capsules and/or fish-oil-enriched substitutes for butter and margarine.     

Mercury and omega-3 fatty acids in retail fish sandwiches

Mercury and fatty acids were measured in fish sandwiches from six retail restaurant chains. Average mercury concentrations ranged from 5 to 132 ppb and were well below the Food and Drug Administration action level (1,000 ppb). The average concentrations of eicosapentaenoic acid plus docosahexaenoic acid ranged from 91 to 620 mg per sandwich. Consuming one or two fish sandwiches per week could result in the consumption of 2 to 40% of the reference dose for mercury for a 60-kg individual and would provide 18 to 126% of the adequate intake for eicosapentaenoic acid plus docosahexaenoic acid as recommended for a pregnant or lactating woman.     

洞庭湖区淡水鱼中有毒有害物残留研究现状

文章对洞庭湖区淡水鱼中有害残留的现状、来源及其在鱼体内的富集方式进行剖析,对该领域今后研究的重点及方向进行展望,以期为后续对洞庭湖区淡水鱼有毒有害残留物的防控防治以及淡水鱼养殖策略的构建提供依据。     

Enrichment of food products with polyunsaturated fatty acids by fish oil addition

Fish oil remains the main dietary source of long chain polyunsaturated fatty acids omega-3, which desirably impact on human health. Increase of omega-3 fatty acids intake is currently recommended. Results of many studies showed that consumption of food products enriched with fish oil offers the potential health benefits, especially in protection against cardiovascular diseases (CVD), cancer and improvement of brain development and function. Health influence, methods, advantages and disadvantages of food enrichment with fish oil as well as characteristics of market of such products were presented.