玛瑙红樱桃果实不同发育阶段香气成分分析

为探究玛瑙红樱桃果实发育过程中香气物质的组成和变化,采用顶空固相微萃取-气相色谱-质谱联用技术对绿熟期、着色期、商熟期和完熟期的挥发性香气成分进行了鉴定,并利用相对气味活度值ROAV评价各香气成分对樱桃果实香气的贡献,以确定关键香气物质。在4个不同发育时期,共检测出114种物质。其中,在绿熟期、着色期、商熟期和完熟期分别检出79、77、44和53种香气物质。绿熟期相对含量最高的是醇类物质,着色期、商熟期和完熟期相对含量最多的均是醛类物质。醛类物质从绿熟期开始便持续不断合成,直至商熟期达到最高值,至完熟期时又略微下降。与之相反的是,酯类物质和醇类物质在果实绿熟期和着色期大量合成,至果实商熟期时骤减至最低值,至完熟期时又略微回升。芳香醛类、C6醛类和C6醇类是构成玛瑙红樱桃最主要的香气组分,相对含量分别占挥发性物质总量的66.22%~96.70%。通过ROAV评价方法,共鉴定出20种关键香气成分,其中壬醛、芳樟醇、己醛是玛瑙红樱桃果实最重要的关键香气成分。具有青香的顺-3-己烯醛是唯一出现在商熟期的特征性关键香气成分。     

不同酿酒葡萄品种C6 醛、醇风味化合物的比较

采用顶空固相微萃取技术(HS-SPME),利用气相色谱- 质谱联用技术(GC-MS)对酿酒葡萄浆果中C6 醛、醇类化合物进行定性、定量分析,比较昌黎葡萄酒产区赤霞珠、品丽珠以及梅鹿辄3 种酿酒葡萄在成熟期六碳醇、醛类风味化合物的变化。结果表明：3 种酿酒葡萄浆果中主要的C6 化合物为己醛、己醇、2- 己烯醛、反-2- 己烯醇、顺-3- 己烯-1- 醇等;建立了定量分析葡萄C6 风味化合物的方法,该方法线性关系良好(R2 ＞ 0.99),检测限小于5μg/L,回收率85%～110%,相对标准偏差(RSD)3%～9%,该方法简易、快速、准确,可用于葡萄样品的测定;不同葡萄品种各C6 醛、醇类化合物含量差异极显著：赤霞珠中含有较多的己醇、反-2- 己烯醇、顺-3- 己烯-1- 醇,显著高于其他品种,品丽珠中己醇、顺-3- 己烯-1- 醇含量最低,而C6 醛类化合物含量则以梅鹿辄含量最高,其次为赤霞珠,品丽珠醛类含量最低;C6 醛类化合物对葡萄香气贡献大,而C6 醇类化合物对葡萄香气贡献小。     

早熟梨果实不同成熟阶段的香气组成

以早熟梨--翠冠、爱甘水、中梨1号为材料,用顶空固相微萃取结合气质联用技术对果实不同成熟阶段的香气组成和含量进行研究。结果表明：3个早熟梨品种不同成熟阶段的果实中醛、醇、酯、酮和烯烃类物质均有检出,但主要香气成分是己醛、2-己烯醛、壬醛、1-己醇和3-己烯-1-醇等醛和醇类物质;果实发育成熟过程中,随着成熟度增加,各品种的香气物质总量均有增加,但各香气成分间存在差异,醛的含量随成熟度的提高而增加,醇的含量除翠冠外均有减少;果实成熟早期爱甘水的香气物质含量最高,成熟后期翠冠的香气物质含量最高,约为其他两品种的2倍。各品种在不同成熟阶段的香气组成和含量表现出各自不同的特点。     

HS-SPME结合GC-MS分析着色香葡萄中挥发性香气成分

利用顶空固相微萃取(HS-SPME)结合气相色谱-质谱联用(GC-MS)分析着色香葡萄中的挥发性香气成分。优化后的HS-SPME条件为:样品超声20 min,采用50/30μm PDMS/CAR/DVB萃取头,样品量8 mL,加盐3 g,40℃萃取40 min。此条件下GC-MS测出36种挥发性香气物质,主要为醇类、醛类、酯类和酮类化合物,其中决定其特征香气的物质包括己醛、2-己烯醛、(E)-2-己烯醇、芳樟醇、脱氢芳樟醇及α-萜品醇等。     

新疆天山北麓产区‘小芒森’葡萄果实成熟过程中香气成分分析

以新疆天山北麓产区‘小芒森’葡萄果实为原料,分别测定五家渠和玛纳斯地区葡萄果实成熟过程（花后8～13周）中的理化指标,采用顶空固相微萃取（HS- SPME）结合气相色谱-质谱（GC-MS）联用技术对其香气物质进行分析,并对其香气物质差异进行偏最小二乘法-判别分析（PLS-DA）。结果表明,在葡萄果实成熟过程中,可溶性固形物含量整体呈上升趋势,而可滴定酸含量呈下降趋势,花后第13周,五家渠、玛纳斯地区葡萄果实可溶性固形物含量分别为30.10 °Bx、27.47 °Bx,可滴定酸含量分别为11.91 g/L、10.67 g/L。在成熟过程中,香气物质整体呈先下降后上升的趋势,两地区葡萄果实共检出香气物质46种,其中,醇类10种,醛类16种,酯类3种,酮类4种,酸类1种,烯类6种,苯类6种。PLS-DA结果表明,导致两地区葡萄果实组分含量差异的主要物质为己醛、E-2-己烯醛、乙酸、己醇。     

2种不同砧木对“美早”大樱桃挥发性物质的影响

比较以"吉塞拉5"和"大青叶"作为砧木的"美早"大樱桃成熟果实香气成分的差异,为大樱桃嫁接生产中砧木的选择提供理论依据。该研究采用固相微萃取结合气相色谱质谱联用仪(GC-MS)的方法对香气成分进行测定分析。结果表明:从2组样品中共检测到31种香气成分,主要为烃类、醇类、醛类和酯类。从砧木为"吉塞拉5"和"大青叶"的"美早"大樱桃成熟果实中分别检测出27种和25种香气成分,各自所特有的香气组分分别为6种和5种,含量较高的是己醛、2-己烯醛、苯甲醛、顺-2-己烯-1-醇、正己醇、苯甲醇等,是"美早"大樱桃成熟果实的特征香气成分。砧木为"吉塞拉5"的"美早"大樱桃成熟果实特征香气成分中己醛、苯甲醛、苯甲醇、反-2-己烯-1-醇乙酸酯的含量均高于"大青叶"砧果实中的含量,可能是造成2种不同砧木樱桃果实风味差异的主要因素之一。     

‘黑宝石’李果实发育期间香气成分的组成及变化

研究‘黑宝石’李果实发育过程中香气成分的组成及变化。采用二氯甲烷直接萃取法提取绿熟期、着色期、商熟期和完熟期果实的香气成分,经气相色谱质谱联用仪进行测定分析。‘黑宝石’李的香气成分共检测到49种,主要有醇类、醛类、酯类、内酯类、酮类、酸类、酚类,还有少量的烃类和胺类化合物。在果实的不同发育时期,香味成分的组成及含量差异较大。醇类主要包括以C6醇类为主的脂肪醇、甾醇以及芳香醇,C6醇类的含量在绿熟期最高,随着果实成熟逐渐降低;甾醇中22,23-二氢-豆甾醇的含量最大,并随着果实成熟逐渐升高。醛类物质在‘黑宝石’李果实中含量最高(29.16%),主要包括C6醛类和芳香醛类,前者的变化同C6醇类;芳香醛类苯甲醛含量随着果实成熟逐渐升高,商熟期达到最高(0.40%),到完熟期又下降至0.29%。酯类和内酯类化合物主要有乙酸酯和γ-十二内酯,它们到商熟期或完熟期才检测出,含量低于1%。除2,3-二氢-香豆酮和十六酸外,酮类化合物(7种)和酸类化合物(3种)只在完熟期出现。酚类化合物主要有2-甲氧基-4-乙烯基苯酚和二叔丁基对甲酚,其相对含量绿熟期最高,完熟期最低。3-羟基-2-丁酮、苯甲醛、十六酸、反式-肉桂酸、乙酸丁酯、乙酸己酯、γ-十二内酯、22,23-二氢-豆甾醇等成分的相对含量随着果实成熟逐渐升高,初步推断是黑宝石李的主要香气成分,对其香气贡献较大。     

两种生物有机肥对红地球葡萄芳香物质组分的影响

对5年生红地球葡萄分别采用0.02%根施和0.01%叶面喷施2种生物有机肥,待果实成熟后,使用固相微萃取技术及气相-质谱联用技术测定葡萄果实的芳香物质含量,以探讨2种生物有机肥对红地球葡萄果实芳香物质组分的影响。结果显示:红地球葡萄果实香气成分主要为醇类、醛类、酮类、酸类、酯类、烷类、苯衍生物和烯类化合物,2种生物有机肥处理的芳香化合物检出数量分别为44种、46种、43种和41种,均高于对照的40种;各处理和对照共同具有的香气成分13种,其中醇类4种,醛类5种,酮类1种,烷类3种,(E)-2-己烯醛、己醛、(E)-2-己烯-1-醇、1-己醇和大马酮是相对含量较高的5种共有芳香化合物;生物有机肥处理显著降低了红地球葡萄果实中的醛类成分相对含量,同时显著提高了醇、酮、酯、烷和烯类成分的相对含量,其中0.02%生物有机肥Ⅱ号根施处理在增加香气化合物数量,提高里那醇、大马酮等重要呈香物质相对含量效果最为显著。     

不同成熟度乍娜葡萄挥发性香气成分分析

采用固相微萃取法,分别使用50/30μmCAR/DVB/PDMS和100μmPDMS萃取头萃取了乍娜葡萄的香气成分。通过比较萃取物质的种类和含量,选定50/30μmCAR/DVB/PDMS为最佳萃取头,并利用该萃取头结合气相色谱质谱联用(GC-MS)技术测定了3种不同成熟度乍娜葡萄的挥发性香气成分。结果表明:乍娜葡萄的香气成分主要由酯类、醇类、醛类和酸类组成,其中含量较高有乙酸乙酯、1-己醇、(E)-2-己烯-1-醇、(E)-2-己烯醛等。随着成熟度的增加,香气成分的总量增加,其中酯类、醛类和酸类总量和相对含量均下降,醇类含量升高。     

顶空固相微萃取-气相色谱-质谱法分析东北油豆角挥发性成分

采用顶空固相微萃取气相色谱-质谱法对东北油豆角挥发性物质进行检测分析,为优质栽培、品质育种及贮藏加工提供参考。结果表明,油豆角挥发成分包括醛、醇、酮、酸、酯、烃、呋喃及醚等类物质。未加工青荚中鉴定出48 种挥发成分,主要为2-己烯醛（相对含量为40.01%）、己醇（12.64%）、己醛（11.40%）,与3-己烯-1-醇、反-2-己烯醛、反-2-顺-6-壬二烯醛、3-甲基-1-丁醇、2-乙基己醇、反,反-2,4-庚二烯醛、反-2-壬烯醛、β-环柠檬醛、肉豆蔻醛等物质共同作用形成青豆荚气味;可食熟荚中鉴定出26 种挥发成分,主要为1-辛烯-3-醇（48.77%）,与顺-4-庚烯醛、3-甲硫基丙醛,反-2-庚烯醛、辛醛、壬醛、香叶基丙酮等共同作用形成油豆角特异
芳香性质。     

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