LC-MS/MS法测定食用油中的辣椒素和二氢辣椒素

建立了用氨基固相萃取小柱净化提取液,液相色谱串联质谱（LC-MS/MS）法测定食用油中辣椒素和二氢辣椒素含量的检测方法。结果表明,辣椒素在0～100 ng/mL范围内线性关系良好（R2 = 0.998 6）,平均回收率在70.6%～90.5%,相对标准偏差（RSD,n=3）在3.1%～8.9%,检出限为0.03 μg/kg;二氢辣椒素在0～20 ng/mL范围内线性关系良好（R2 = 0.998 8）,平均回收率在71.5%～100.7%,相对标准偏差（RSD,n=3）在6.0%～13.2%,检出限为0.006 μg/kg。该方法简便快速、准确可靠,是鉴别地沟油和测定食用油中辣椒素类物质的有效方法。     

超高效液相色谱-串联质谱法测定食用油脂中辣椒素

目的 建立一种超高效液相色谱-串联质谱测定食用油脂中辣椒素的分析方法。方法 试样经正己烷溶解,氢氧化钠水溶液提取,碱性提取液经硫酸酸化后,过PEP-2固相萃取小柱净化,采用超高效液相色谱－串联质谱仪检测,外标法定量。以ACQUITY UPLC BEH C18色谱柱(3.0mm×100mm,1.7μm)为固定相,以0.1%甲酸水溶液和0.1%甲酸乙腈溶液为流动相进行梯度洗脱,串联质谱分析中采用电喷雾离子源正离子模式和多反应监测模式。结果 天然辣椒素、二氢辣椒素、合成辣椒素的质量浓度在0.1μg/L~100μg/L内与其对应的峰面积呈线性关系,检出限(3S/N)合成辣椒素为0.01 μg/kg;天然辣椒素为0.006 μg/kg;二氢辣椒素为0.005 μg/kg。以空白样品为基体进行加标回收试验,回收率在80.3%～96.2%,测定值的相对标准偏差(n=6)为4.5%～5.6%。结论 该方法快速、准确,能满足食用油脂中辣椒素的快速筛查和检测要求。     

辣椒中辣椒素类物质的检测方法及稳定性研究

目的:通过对GB/T 21266-2007中辣椒素和二氢辣椒素检测的色谱条件的优化,使辣椒素和二氢辣椒素的测定更加快速,并考察辣椒素与二氢辣椒素贮存过程中的稳定性。方法:高效液相色谱法,色谱条件为C18色谱柱(4.6mm×250mm,5μm),流动相为甲醇∶水(V∶V=70∶30),流速为1mL/min,检测波长为280nm,进样量10μL,柱温30℃。结果 :与GB/T 21266-2007的色谱条件相比,检测时间缩短了约12min。提取出的辣椒素与二氢辣椒素在室温条件下贮存一个月,其含量没有发生剧烈波动。结论:此色谱条件能对辣椒素和二氢辣椒素进行有效检测,且能明显缩短两者的保留时间;提取出的辣椒素与二氢辣椒素室温条件下短时间内能保持稳定。     

超高效液相色谱-四极杆/静电场轨道阱质谱快速筛查和定量检测食用油脂中的天然辣椒素、合成辣椒素和二氢辣椒素

建立超高效液相色谱-四极杆/静电场轨道阱质谱(UHPLC-Q/Orbitrap)快速筛查和定量检测食用油脂中天然辣椒素、合成辣椒素和二氢辣椒素的分析方法。结果表明,前处理最佳条件为:样品经二氯甲烷溶解,氢氧化钠水溶液提取,硫酸酸化,PRiME HLB固相萃取小柱净化;液质最佳条件为:0.1%甲酸水-0.1%甲酸乙腈梯度洗脱,Thermo Scientific Accucore Vanquish C₁₈+色谱柱(100 mm×2.1 mm,1.5 μm)分离,静电场轨道阱质谱分析检测。结果表明:3种辣椒素在0.1~40 μg/L范围内线性关系良好,R2≥0.999;3个加标水平(n=6)的平均回收率在66.7%~112.8%范围内,相对标准偏差在3.2%~9.7%范围内;检出限在0.02~0.05 μg/kg之间,定量限在0.1~0.2 μg/kg之间。该方法可在无标准物质的情况下对食用油脂中3种辣椒素进行快速筛查及确证,同时可在有标准物质下进行准确定量,为食用油脂中非法添加回收油脂的筛查确证和准确定量检测提供新的技术和思路。     

辣椒不同成熟期辣椒素、二氢辣椒素含量的变化

[目的]研究辣椒素、二氢辣椒素的分析方法,测定辣椒中3个不同成熟期辣椒素、二氢辣椒素含量,分析其变化规律.[方法]采用高效液相色谱进行分离,并鉴定其成分及含量.色谱条件:Shimadzu C18色谱柱(250mm×4.6mm,51μm),流动相:甲醇-重蒸水(4:1),流速:0.8mL/min,检测波长:280nm,柱温:30℃,进样量:10μL.峰面积与待测物浓度呈良好的线性关系,辣椒素标准曲线的回归方程是Y=8333309X+464.34,相关系数为0.9999.二氢辣椒素标准曲线的回归方程是Y=6386890X+2962.65,相关系数为0.9999.回收率在91.34%～95.94%之间.[结果]高效液相色谱法可以使辣椒中的辣椒素、二氢辣椒素完全分离并定性、定量分析.实验结果表明,随着辣椒成熟度的增加,辣椒素、二氢辣椒素的含量逐渐增加.[结论]本研究可以用于HPLC快速测定辣椒中辣椒素、二氢辣椒素.     

高效液相色谱法测定辣椒制品中的辣椒素类物质

该研究采用了高效液相色谱法对辣椒制品中的辣椒素类物质进行检测,并对其提取条件和检测方法进行了研究。以乙醇∶水＝70∶30（V∶V）作为提取液,采用直接萃取法提取样品中的辣椒素和二氢辣椒素,以0.3%磷酸二氢钾溶液-乙腈（62:38,V:V）为流动相,检测波长230 nm,Macherey-Nagel Nucleosil120-5 C18色谱柱（4.6 mm×250 mm, 5 μm）分离。结果表明,辣椒素和二氢辣椒素在20～100 μg/mL质量浓度范围线性关系良好（R12 = 0.999 8,R22 = 0.999 9）,检出限为0.001 g/kg,加标回收率分别为93%～104%和86%～103%,相对标准偏差RSD＜5%。该方法操作简单、快速,具有良好的准确性和精密度,可有效排除香辛料物质的杂峰干扰,适合各类辣椒制品中辣椒素类物质的检测。     

高效液相色谱法测定豆瓣中辣椒素类物质含量

豆瓣是以蚕豆和辣椒作为主要原料生产的一种调味品,是西南地区尤其是四川地区的一种传统发酵食品。为了测定豆瓣中的辣味物质(辣椒素及二氢辣椒素),建立了高效液相色谱快速检测方法:色谱柱为C18反相色谱柱(250mm×4.6mm,5μm),流动相为甲醇和水(V/V,75∶25),流速1.0mL/min,柱温30℃,进样量20μL,检测波长280nm。辣椒素类物质的提取采用超声波辅助提取。结果表明:豆瓣样品中辣椒素含量在0.0161～0.0624g/kg之间,二氢辣椒素的含量在0.0142～0.0357g/kg之间,斯科维尔指数在519～1671SHU之间。     

酶法提取辣椒素的实验探讨

使用酶法提取辣椒素的新方法研究了最佳酶解条件,通过酶解液初始pH值、酶解时间、酶解温度和酶量的三水平正交实验,得到了影响辣椒素产量指标的最优水平组合,实验得出辣椒素产量为7.18mg/g;并与传统溶剂浸提法提取辣椒素进行了比对实验,结果表明:酶法提取辣椒素萃取速度快、效率高,产量比传统方法提高了30%.     

固相萃取-液相色谱-串联质谱法测定食用油脂中的合成辣椒素、天然辣椒素和二氢辣椒素

摘要：建立了食用油脂中天然辣椒素、合成辣椒素和二氢辣椒素的固相萃取-液相色谱-串联质谱(HPLC-MS/MS)检测方法。样品经2%氢氧化钠溶液提取,C18固相萃取小柱净化后,进高效液相色谱-串联质谱仪,采用乙腈和0.1%甲酸水溶液作为流动相进行梯度洗脱,多反应监测（MRM）在正离子模式下进行质谱扫描,对3种辣椒素进行定量测定。结果表明,合成辣椒素、天然辣椒素和二氢辣椒素在0.5~50 ng/mL质量浓度范围线性关系良好,相关系数大于0.999 0,三者检出限分别为0.05、0.03、0.03 μg/kg,回收率在71.2%~87.5%之间,相对标准偏差小于4.0%。该方法快速、准确,灵敏度高,能有效满足实验室对食用油脂中非法添加餐厨废油的定量检测。     

高效液相色谱法测定辣椒素及二氢辣椒素

采用超声波辅助甲醇提取辣椒中的辣椒素、二氢辣椒素,高效液相色谱法进行测定。色谱条件：ShimAdzuC18色谱柱（250mm×4．6mm,5μm）,流动相为甲醇-重蒸水（4：1）,流速0．8ml／min,检测波长280hm,柱温;30℃,进样量10μl。峰面积与待测物浓度呈良好的线性关系,辣椒素标准曲线的回归方程是Y=8333309X＋464．34,相关系数为0．9999。二氢辣椒素标准曲线的回归方程是Y=6386890X＋2962．65,相关系数为0．9999。回收率在91．34％～93．94％之间。结果表明,209种不同样品中的辣椒素含量在0．0094～34．99mg／g之间,二氢辣椒素含量在0．0011～24．68mg／g之间。本方法可以用于HPLC快速测定辣椒中辣椒素、二氢辣椒素。     

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