气相色谱法测宝石鱼鱼油中的脂肪酸组成

本文以宝石鱼为原料，利用气相色谱法来鉴定宝石鱼鱼油中的的脂肪酸组成，通过与标准脂肪酸色谱图比较共确定25种脂肪酸，其中以16：0、18：0、18：1n-9、18：2n-6、22：6n．3、20：4n．3、22：5n-3(EPA)和22：6n-3(DHA)为主。     

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。     

沪浙地区不同泌乳期母乳脂肪酸组成及分布研究

研究了我国沪浙地区不同泌乳期(0～1,1～3,3～6和6～12月)母乳总脂肪酸、甘油三酯sn-2位脂肪酸和磷脂脂肪酸组成及分布。结果显示,随着泌乳期的延长,母乳脂肪中的中链饱和脂肪酸(MCSFA)、C_(12:0)和C_(14:0)含量逐渐升高,多不饱和脂肪酸(PUFA)、C_(18:2n-6)(LA)和C_(18:3n-3)(ALA)含量先升高后下降,C_(20:4n-6)(ARA)和C_(22:6n-3)(DHA)含量先显著下降而后趋于稳定,而饱和脂肪酸(SFA)、C_(16:0)和C_(18:0)含量几乎没有变化。母乳脂肪酸在甘油三酯结构中的位置分布具有独特性:MCSFA、SFA、C_(12:0)、C_(16:0)、ARA和DHA主要结合在sn-2位上,而MUFA、C_(18:1n-9)、PUFA、LA和ALA主要分布在sn-1,3位上,且这种独特的位置分布几乎不随泌乳期的变化而变化。母乳磷脂脂肪酸中的ARA和DHA含量尽管在不同泌乳期之间有所差异,但均显著高于其在母乳总脂肪酸中的含量。研究结果为我国婴儿配方乳粉的脂质母乳化特别是结构母乳化提供了重要的数据支撑。     

3种海参与3种贝类中脂肪酸及烯醚键基团的 气相色谱/质谱分析比较

本文研究了用气相色谱/质谱法测定比较3种海参与3种贝类脂肪酸及脂肪醛二甲基缩醛的方法。该6种原料经Folch法提取总脂,用10%硫酸-甲醇溶液对其进行甲酯化反应,通过气相色谱/质谱法对其脂肪酸及脂肪醛二甲基缩醛的组成进行分析。实验结果表明：10%硫酸-甲醇溶液能有效地对脂肪酸进行甲酯化衍生;同时促使烯醚键断裂,并与甲醇发生缩醛反应生成脂肪醛二甲基缩醛。通过气相色谱/质谱分析,从3种海参与3种贝类的气相色谱/质谱图中共鉴定出24种脂肪酸,海参中脂肪酸以C16:0,C16:1(n-7)和C20:4(n-6)为主;贝类中脂肪酸以C16:0,C20:5(n-3)和C22:6(n-3)为主;海参与贝类中脂肪醛二甲基缩醛均以C18:0DMA为主。海参和贝类中的脂肪酸及脂肪醛二甲基缩醛的组成与含量都相差较大。     

3种海参与3种贝类中脂肪酸及烯醚键基团的气相色谱/质谱分析比较

目的采用气相色谱/质谱法测定比较3种海参与3种贝类脂肪酸及脂肪醛二甲基缩醛的方法。方法6种原料经Folch法提取总脂,用10%硫酸-甲醇溶液对其进行甲酯化反应,通过气相色谱/质谱法对其脂肪酸及脂肪醛二甲基缩醛的组成进行分析。结果 10%硫酸-甲醇溶液能有效地对脂肪酸进行甲酯化衍生,同时促使烯醚键断裂,并与甲醇发生缩醛反应生成脂肪醛二甲基缩醛。通过气相色谱/质谱分析,从3种海参与3种贝类的气相色谱/质谱图中共鉴定出24种脂肪酸,海参中脂肪酸以C16:0,C16:1(n-7)和C20:4(n-6)为主;贝类中脂肪酸以C16:0,C20:5(n-3)和C22:6(n-3)为主;海参与贝类中脂肪醛二甲基缩醛均以C18:0DMA为主。结论海参和贝类中的脂肪酸及脂肪醛二甲基缩醛的组成与含量相差较大。     

青花鸡、茶花鸡2号和白羽肉鸡肌肉脂肪酸含量比较分析

为研究青花鸡、茶花鸡2号和白羽肉鸡3种鸡肌肉中脂肪酸含量差异,先采用氯仿-甲醇法对鸡肉粉进行脂肪提取,并对脂肪提取物进行甲酯化处理,再应用高效气相色谱仪检测3种鸡肌肉中的18种脂肪酸.结果表明:3种鸡肌肉脂肪酸均以棕榈酸(C16∶0)、硬脂酸(C18∶0)、油酸(C18∶1 n-9c)和亚油酸(C18∶2 n-6c)为...     

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)。     

质谱特征离子定性分析海洋鱼油中的脂肪酸组成

研究质谱特征离子对海洋鱼油脂肪酸的快速定性分析。首先,根据脂肪酸甲酯的断裂规律,基峰离子可快速确定脂肪酸的不饱和度,如基峰离子m/z 74为饱和脂肪酸,m/z 55为单烯脂肪酸,m/z 67为二烯脂肪酸,m/z 79为三烯及以上多不饱和脂肪酸;其次,分子离子M+及其特征性碎片丢失而形成的特征离子如[M-29]~+、[M-31]~+、[M-32]~+、[M-43]~+和[M-74]~+等,可有效用于脂肪酸甲酯分子量和脂肪酸碳链长度的分析;而ω离子和α离子可准确对三烯及以上多不饱和脂肪酸中的双键位置进行分析鉴定。通过质谱特征离子的综合分析,从海洋鱼油胶囊中共分析鉴定出24种脂肪酸,以C_(14:0)、C_(16:0)、C_(18:1n-9)、C_(20:5n-3)和C_(22:6n-3)为主,表明质谱特征离子能快速准确用于海洋鱼油脂肪酸的定性分析。同时,海洋鱼油中C_(20:5n-3)和C_(22:6n-3)的总含量高达29.13%,表明其具有很高的营养价值和保健功能。     

裂殖壶菌油脂成分及抗氧化活性分析

为研究裂殖壶菌油脂成分及抗氧化活性,本文采用气相色谱-质谱和核磁共振技术分别对裂殖壶菌油脂的脂肪酸组成和脂质成分进行分析,并对油脂的自由基清除能力和总抗氧化能力进行测定。结果表明：裂殖壶菌油脂的脂肪酸组成简单,主要为C14:0(13.22%)、C16:0(26.78%)、C22:5n-6(DPA,13.66%)和C22:6n-3(DHA,42.04%);其脂质成分以甘油三酯为主,含有少量游离脂肪酸,且C22:6n-3和C22:5n-6等多不饱和脂肪酸主要结合于甘油三酯的sn-2位。同时,裂殖壶菌油脂具有较好的DPPH、ABTS⁺和羟基等自由基清除能力和总抗氧化能力,且在10～50 mg/mL质量浓度范围内呈现显著的量效关系(P<0.05)。裂殖壶菌油脂富含C22:6n-3和较好的抗氧化活性,具有较高的营养价值和功能油脂开发潜力。本研究为裂殖壶菌油脂成分分析、抗氧化活性评价以及功能性油脂开发提供了理论依据。     

三种硅藻产多不饱和脂肪酸分析

采用f/2培养基,对3种硅藻:牟氏角毛藻(Chaetoceros mualleri)、三角褐指藻(Phaeoda-ctytuum tricornutum)、硅藻舟形藻(Navicala incerta)进行培养及脂肪酸组成研究。牟氏角毛藻和三角褐指藻的生长周期短,生物量较高。3种硅藻的脂肪酸组成相近,主要的脂肪酸是C14:0,C16:0,C16:1(n-7)和C20:5(n-3),多不饱和脂肪酸中C20:5(n-3)(EPA)含量最高,其中三角褐指藻中的EPA含量达到11.7%。3种硅藻的DHAC22:6(n-3)含量都较低。通过调整三角褐指藻和牟氏角毛藻的培养条件,可以提高EPA含量,作为优良的水产饵料。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the