GC-MS-O结合OAV鉴定花生油特征香气成分

该研究利用气相色谱-质谱联用（GC-MS）、气相色谱-嗅闻（GC-O）、气味活性值（OAV）和香气重组对花生油的特征香气成分进行评价分析。得到顶空固相微萃取最优条件为DVB/CAR/PDMS萃取头、萃取温度50℃、萃取时间60 min。在此条件上,在花生油中共检测出89种挥发性化合物,包括吡嗪、呋喃、醛、酚、吡咯、吡啶、酮、醇、酸、酯类等化合物。其中GC-O确定的香气活性化合物32种,结合OAV分析得到特征香气成分27种。热榨花生油和冷榨花生油中的特征香气成分分别有22、8种,共有成分为己醛、乙酸和苯甲醛。热榨花生油的特征香气成分主要为2,6-二甲基吡嗪、2,3-二甲基吡嗪、2-乙基-6-甲基吡嗪、2-乙基-5-甲基吡嗪、2,3,5-三甲基吡嗪、3-乙基-2,5-二甲基吡嗪、2-乙基-3,5-二甲基吡嗪、苯甲醛、乙酰基吡嗪、2,4-癸二烯醛、麦芽酚、甲基环戊烯醇酮、2-乙酰基吡咯、吡咯-2-甲醛、2-甲氧基-4-乙烯基苯酚。冷榨花生油特征香气成分主要为己醛、D-柠檬烯等物质。结果预期对评价花生油的品质及优化其加工工艺具有重要意义。     

花生油挥发性风味成分的鉴定

采用顶空固相微萃取法(HS-SPME)制备样品,利用气相色谱-质谱(GC-Ms)对花生油的挥发性风味成分进行了分离鉴定,共得到53种成分,占总检出化合物的86.23%.主要是吡嗪、吡啶、呋喃等含氮、氧杂环化合物.其中吡嗪类化合物含量最高,占总挥发性成分的32.89%.     

基于全二维气相色谱-飞行时间质谱分析技术分析南北派大清香白酒挥发性风味物质差异

研究以黄鹤楼大清香和汾酒为主要研究对象,采用全二维气相色谱-飞行时间质谱（comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry,GC×GC-TOF MS）技术对六种南北派大清香白酒的挥发性成分进行分析,在6种样品中共筛选出302种香气贡献度较高的挥发性化合物,其中种类最多的是酯类化合物,共检测到88种,其次是醇类化合物检测到52种,机酸类化合物18种,醛酮类化合物47种,烃类化合物32种,呋喃类化合物8种,萜烯类化合物9种,芳香族化合物40种,吡嗪类化合物3种,其他类化合物5种。由于呋喃类和萜烯类化合物通常具有特殊的香气,对清香型白酒的香气产生重要影响,因而,本文在鉴定出的挥发性香气组分中着重对比分析了呋喃类和萜烯类。通过GC×GC-TOFMS技术在六种清香型白酒中确定出40种主要区分南北派大清香白酒香气的差异性挥发物质,其中酯类化合物4种,醇类化合物14种,醛酮类化合物15种,芳香族化合物4种,稀萜类化合物1种,其他类化合物2种。该研究为清香型白酒的挥发性香气组分分析与感官特...     

同时蒸馏萃取法提取花生油挥发性物质的研究

采用同时蒸馏萃取法结合气相色谱-质谱分析技术（SDE-GC-MS）,对水酶法制备的花生油挥发性物质进行提取和分析,优化同时蒸馏萃取条件。结果表明：花生油总挥发性化合物种类及吡嗪类化合物相对含量均随样品量的增加而增加;二氯甲烷作为萃取溶剂萃取得到的总挥发性化合物种类及吡嗪类化合物相对含量较乙醚多;在花生油用量为30 g时,采用二氯甲烷可以萃取出66种化合物,经质谱分析可鉴定出42种化合物,其中吡嗪类化合物有6种,占总挥发性成分6.73%。     

马铃薯蛋糕常温贮藏期间香气成分动态变化

采用顶空固相微萃取-气相色谱-质谱联用技术,分析马铃薯蛋糕在常温贮藏过程中香气成分动态变化。GCMS分析表明:样品共检出香气成分82种,其中醛类21种、醇类16种、杂环类化合物14种、酯类9种、酮类7种、酸类7种、烃类6种、含硫化合物1种、酚类化合物1种。蛋糕在1h、24h、72h、120h、168h贮藏期间,分别分离鉴定出50、56、62、68、60种香气物质,分别占总峰面积91.08%、92.77%、93.93%、95.96%、84.55%,醛类、醇类、杂环类化合物是蛋糕贮藏期间的主体香气成分,主要包括己醛、庚醛、壬醛、3-甲基丁醛、苯甲醛、丙二醇、1-辛烯-3-醇、2-甲基吡嗪、2,3-二甲基吡嗪、2,5-二甲基吡嗪、4,6-二甲基嘧啶、2-戊基呋喃、糠醛、糠醇等。由此看出,不同贮藏时间蛋糕香气成分构成及相对含量变化差异显著,蛋糕在贮藏120h时香气化合物数量和相对含量达到最高值。     

固相微萃取-气质联用技术测定5种食用植物油挥发性成分

目的采用气相色谱-质谱(GC-MS)对大豆油、芝麻油、花生油、橄榄油、葡萄籽油5种食用植物油中挥发性成分进行分析。方法采用顶空固相微萃取(HS-SPME)技术对5种食用植物油中的挥发性成分进行萃取,并结合气相色谱-质谱(GC-MS)技术对挥发性成分进行测定。结果 5种食用植物油中共检测出101种挥发性化合物,其中大豆油11种、花生油28种、芝麻油65种、橄榄油25种、葡萄籽油5种。主要包括醛类、酯类、醇类、杂环类、酚类、酸类等10类物质。大豆油中主要的挥发性成分有戊醛、已醛和己酸,花生油中主要的挥发性成分有己醛、2,5-二甲基吡嗪和2,3-二氢苯并呋喃;芝麻油中主要的挥发性成分为5-甲基呋喃醛、2-吡咯甲醛、糠醇、愈创木酚、2-甲基吡嗪、2-乙基-6甲基吡嗪等;橄榄油中主要的挥发性成分为叶醇和4-己烯-1-醇乙酸酯;葡萄籽油中主要的挥发性成分为已醛。结论 5种食用植物油的挥发性物质的种类和含量上有很大区别,可为食用植物油的掺假鉴别提供参考依据。     

应用顶空固相微萃取-气相色谱质谱技术解析酿造用高粱蒸煮挥发性香气成分

通过比较不同样品前处理方法提取分析蒸熟高粱中香气组分的效果,开发出基于瓶内蒸煮结合顶空固相微萃取-气相色谱质谱联用(headspace solid phase microextraction and gas chromatography mass spectrometry,HSSPME-GC-MS)分析酿造用高粱蒸煮香气组分的方法。采用该方法研究了白酒酿造主要原料高粱蒸煮后挥发性香气特征。在蒸熟的高粱中共鉴定出46种挥发性香气成分,包括醛类化合物16种,有机酸类化合物7种,醇类化合物6种、酯类化合物6种,酚类化合物4种、酮类化合物2种、呋喃类化合物2种、其他类化合物3种。其中峰面积相对含量较高的化合物有苯甲醛(20.21%),己酸(9.00%),壬醛(8.66%),糠醛(8.90%),2-戊基呋喃(6.48%)和萘(5.49%)。同时还检测到一批香气阈值较低的化合物,如壬醛、(E,E)-2,4-癸二烯醛、(E)-2-辛烯醛、(E)-2-癸烯醛、1-辛烯-3-醇、香兰素、4-乙基愈创木酚、4-乙烯基愈创木酚、γ-辛内酯、γ-壬内酯等。这些香气物质可能是构成酿造用高粱蒸煮香气特征的主要香气组分。     

不同植物油对植物肉风味及感官特性的影响

为探究不同脂肪酸组成的植物油对植物肉风味及感官品质的影响,将常用于食品加工且脂肪酸组成差异较大的5种植物油(菜籽油、大豆油、花生油、葵花籽油、棕榈油)添加到植物肉中,采用顶空固相微萃取-气相色谱-质谱联用技术(HS-SPME-GC-MS)对其进行风味分析,结合感官评价和质构分析等方法对5组植物肉进行对比。实验结果表明,5组植物肉的挥发性成分、感观属性、质构特性等存在显著差异。5组样品中共鉴定出79种挥发性组分,其中30种可被嗅闻到,主要包括吡嗪类、呋喃类、醛类、含硫类化合物。2,3,5-三甲基吡嗪、2-戊基呋喃、3-甲硫基丙醛等化合物的嗅闻强度最大。与其他样品相比,添加花生油的样品C和添加菜籽油的样品A中挥发性化合物种类和含量较多,但样品C的香气轮廓中油脂味较为突出,且该组样品的硬度与胶黏性较差,并不适用于植物肉的生产制作。样品A以肉香味为主,其硬度、弹性较大。研究结果表明,含芥酸、油酸较多的菜籽油更适用于植物肉的加工生产,对植物肉的风味、质构等感官品质具有明显增强作用。     

浓香葵花籽油挥发性风味成分的鉴定

采用顶空固相微萃取法（HS-SPME）萃取葵花籽油的挥发性风味物质,优化了萃取条件,采用气相色谱-质谱联用（GC-MS）对其进行分离鉴定。结果表明,萃取温度50℃和萃取时间50min下解吸5min萃取效果最好,经数据库检索,葵花籽油中共鉴定出97种化合物,占总检出化合物的83.14%,包括吡嗪、呋喃、醛、酯和酸等化合物。初步判断葵花籽油主要香气成分中包含2-戊基呋喃和2,5-二甲基吡嗪。      

浓香型白酒堆积发酵酒醅挥发性成分分析

采用索氏提取法结合气质联用技术,对浓香型白酒堆积发酵酒醅的微量成分进行初步定性分析研究,共检出82种化合物,其中酯类化合物45种、酸类12种,占挥发性成分总数的69.51%,它们是浓香型白酒主要的香气成分。此外,愈创木酚类(5种)、呋喃类(3种)、芳香族类(8种)以及吡嗪类化合物(2种)也为浓香型白酒的复合香气作出了重要贡献。实验结果表明,浓香型白酒采用堆积发酵工艺,有利于增加白酒中的香味成分,使香气更加芳香浓郁、丰满协调。     

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