西藏牦牛酥油脂肪酸成分分析及功能特性评价

通过脂肪酸组成分析来评价国产牛乳乳脂和西藏牦牛酥油的营养功能特性。结果表明,藏酥油与国产奶粉和纯奶脂肪中的饱和脂肪酸、不饱和脂肪酸含量差异不大,但酥油中的功能性脂肪酸含量明显高于国产纯奶和奶粉。藏酥油共轭亚油酸约为国产奶粉的3倍,二十碳五烯酸(EPA)、二十二碳六烯酸(DHA)仅存在于藏酥油中;国产奶粉和纯奶脂肪中的α-亚麻酸(LNA)仅为藏酥油的1/7~1/4;花生四烯酸(AA)国产奶粉和纯奶也仅有藏酥油的约1/2。     

二十二碳六烯酸(DHA)、二十碳五烯酸(EPA)、亚油酸、亚麻酸和花生四烯酸(AA)在婴幼儿配方奶粉中的测定

建立了气相色谱法同时测定婴幼儿奶粉中的DHA,EPA,亚油酸,亚麻酸和花生四烯酸AA含量的方法。采用色谱柱为脂肪酸型色谱柱DB-23,氢火焰离子化检测器（FID）,优化了色谱条件。结果表明,DHA,EPA,亚油酸,亚麻酸和花生四烯酸AA分离效果很好。DHA的最低检出限为0.02g/L,回收率为99.8%,变异系数为0.88%;EPA的最低检出限为0.01g/L,回收率为94.9%,变异系数为1.01%;亚油酸的最低检出限为0.02g/L,回收率为97.7%,变异系数为0.80%;亚麻酸的最低检出限为0.01g/L,回收率为99.9%,变异系数为0.95%;AA的最低检出限为0.01g/L,回收率为98.9%,变异系数为0.93%。     

气相色谱法同时测定保健食品中的5种 不饱和脂肪酸

目的建立气相色谱法同时测定保健食品中亚油酸、α-亚麻酸、二十碳五烯酸(eicosapentaenoic acid,EPA)、二十二碳六烯酸(docosahexaenoic acid,DHA)和二十二碳五烯酸(docosapentaenoic acid,DPA)的含量。方法样品先采用氢氧化钾甲醇溶液进行皂化处理,再用三氟化硼甲醇溶液甲酯化,经HP-FFAP色谱柱(30m×0.53 mm,1.0μm)分离测定。结果 EPA甲酯、DHA甲酯、DPA甲酯、亚油酸甲酯、α-亚麻酸甲酯分别在0.03927~1.178、0.04200~1.260、0.03449~1.035、0.08368~1.255、0.08482~4.241 mg/mL的浓度范围内线性关系良好,相关系数r均大于0.999;检出限分别为0.0039、0.0042、0.0034、0.0042、0.0042 mg/mL;加标回收率在91.1%~109.3%之间,相对标准偏差均小于5%。结论该方法操作简单快捷,适用于保健食品中亚油酸、α-亚麻酸、EPA、DPA和DHA的测定。     

乙酰氯-甲醇甲酯化法测定婴幼儿配方乳粉中脂肪酸含量方法的优化

目的改进乙酰氯-甲醇甲酯化气相色谱(gas chromatography,GC)法测定婴幼儿配方乳粉中脂肪酸含量的方法。方法改进了乙酰氯-甲醇配制的体积浓度,考察了不同甲酯化反应温度和时间对月桂酸、肉豆范酸、亚油酸(linoleic acid,LA)、α-亚麻酸(α-linolenic acid,α-LA)、二十二碳六烯酸(docosahexaenoic acid,DHA)和花生四烯酸(arachidonic acid,AA)含量测定的影响,并验证了改进方法的检出限、重现性和回收率等。结果采用改进的乙酰氯-甲醇配制液可将甲酯化反应时间缩短至60 min,在4℃下保存该配制液有效期达10 d。各组分在一定质量浓度范围内线性关系良好(r>0.999)。改进方法中月桂酸、肉豆蔻酸、亚油酸、α-亚麻酸、二十二碳六烯酸和花生四烯酸的检出限为0.11~0.68 mg/100 g,定量限为3.3~20.4 mg/kg,与国标方法相比定量限提升了38.2%~95.0%,回收率均在95%~105%之间,稳定性相对标准偏差为0.79%~2.59%。结论改进方法能满足婴幼儿配方乳粉中脂肪酸含量的检测。     

婴幼儿奶粉中亚麻酸、亚油酸、花生四烯酸和二十二碳六烯酸的测定

采用气相色谱法测定婴儿配方乳粉中亚麻酸(LA)、亚油酸(LNA)、花生四烯酸(AA)和二十二碳六烯酸(DHA)含量。试验结果表明:LA、LNA、AA和DHA分离效果较好,得到LA,LNA,AA和DHA的检出限分别为0.057、0.06、0.085和0.25μg/mL;其重复性在0.64%～5.46%之间,回收率在82.1%～105.7%之间。     

利用脂肪酶制取富含多不饱和脂肪酸油方法

<正>1 前言 我们知道,共轭亚油酸(CLA)、α-亚麻酸(ALA)、γ-亚麻酸(GLA)、双高γ-亚麻酸(DGLA)、花生四烯酸(AA)、二十碳五烯酸(EPA)、二十二碳五烯酸(DPA)、二十二碳六烯酸(DHA)等各种多不饱和脂肪酸(PUFA)对人体具有各种不同生理活性,因国内外已有许多论文阐述,不再赘述。     

婴幼儿配方食品和乳粉中DHA、EPA、亚油酸、亚麻酸和花生四烯酸(AA)的测定

建立了气相色谱法同时测定乳制品中DHA，EPA，亚油酸，亚麻酸和花生四烯酸AA含量的方法。采用色谱柱为脂肪酸型色谱柱DB-23，氢火焰离子化检测器。优化了色谱条件。结果表明，DHA，EPA，亚油酸，亚麻酸和花生四烯酸AA分离效果很好。DHA的最低检出限为0．02g／L，回收率为100．1％，变异系数（CV）为0．82％；EPA的最低检出限为0．01g／L，回收率为99．8％，变异系数为1．04％；亚油酸的最低检出限为0.01g／L，回收率为99．7％，变异系数为0．82％；亚麻酸的最低检出限为0．01g／L，回收率为99．7％，变异系数为0．96％；AA的最低检出限为0．01g／L，回收率为99．9％，变异系数为0．96％。     

微生物多价不饱和脂肪酸的研究

一、多价不饱和脂肪酸的生理活性及功能多价不饱和脂肪酸（Polvunsaturatedfattyacids）是指含有两个或两个以上双键且碳链长为16至22个碳原子的直链脂肪酸，它主要包括r-亚麻酸（GLA），二高r-亚麻酸（DHLA）、花生四烯酸（AA）、二十碳五烯酸（EPA）、二十二碳六烯酸（DHA）等，以其独特的生物活性，引起了人们极大的兴趣。[1][2]多价不饱和脂肪酸根据其距离脂肪酸中性末端（W端）的第一个双键位置不同，分为n－6和n—3两大系列。[3]n－6系列是由亚油酸衍生而来，其主要体内代谢物有r一亚麻酸、二高r-亚麻酸、花生四烯酸。n－3系列…     

罗非鱼眼脂肪酸的分析

以罗非鱼加工下脚料鱼眼为原料,冷冻干燥后采用Soxhlet提取法提取其中脂肪,用氢氧化钾-甲醇法甲酯化后利用气相色谱-质谱联用仪进行分析测定。结果表明:罗非鱼眼脂肪含量为84.35%(以DM计),其中含有27种脂肪酸,不饱和脂肪酸有11种,相对百分含量占检出所有脂肪酸的74.06%,其中油酸占32.59%,亚油酸(LA)占17.76%,α-亚麻酸占3.32%,二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)的含量分别为1.06%和2.54%,测定结果为罗非鱼眼的深加工提供了科学依据。     

海鳗肌肉脂肪酸组成及干燥对其影响

从海鳗肌肉所得鱼油经过甲酯化,用GC-MS进行了脂肪酸的组成分析,共鉴定出19种脂肪酸,其主要成分为棕榈酸,棕榈油酸,硬脂酸,油酸,花生四烯酸,二十二碳六烯酸(DHA)和二十碳五烯酸(EPA).同时通过GC来考察真空干燥和热风干燥对脂肪酸组成的变化,结果表明采用热风干燥优于真空干燥.经过真空干燥以后,多不饱和脂肪酸量减少,特别是DHA和EPA分别减少21.5%和18.6%,降低了海鳗制品的营养价值.     

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.     

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     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press