高效毛细管电泳法快速测定乳制品中三聚氰胺

建立高效毛细管电泳快速测定乳制品中三聚氰胺含量的方法。样品用100mmol/L 醋酸提取,以150mmol/L磷酸二氢钠为分离缓冲液,以未涂敷石英毛细管(20cm(有效长度)× 50μm)为分离柱,于235nm 波长处检测,采用峰面积外标法定量。实验研究缓冲溶液的浓度、分离溶液pH 值及样品前处理条件对三聚氰胺准确定量的影响。方法检出限为0.06mg/L,定量限为0.2mg/L,线性范围为0.2～200mg/L,线性相关系数r=0.9998。1.0、10mg/L 添加水平的平均加标回收率分别为93.0% 及84.3%。该方法简单快速,6min 之内即可完成一次样品分析(预清洗2min,分离4min)且试剂消耗少、环境友好及检测准确,适合于各类乳制品中三聚氰胺的常规测定。     

离子色谱-脉冲安培法测定白酒中氰化物

目的建立离子色谱-脉冲安培法检测白酒中氰化物含量的方法。方法白酒样品稀释10倍后直接进样,以氢氧化钾溶液(12 mmol/L)进行等梯度淋洗,采用银工作电极,以Ag/AgCl复合参比电极模式,脉冲安培三点位波形方式进行检测。结果该方法在5～200μg/L浓度范围内线性关系良好,相关系数R~2为0.999 9。该方法对白酒类基质检出限为3.5μg/L,定量限为9.5μg/L。对不同类型白酒样品,在10、30和50μg/L三个加标浓度水平下回收率在91.7%～102.0%之间。日内相对标准偏差(RSD)在2.2%～4.8%之间,日间RSD在1.5%～1.9%之间。本方法与GB 5009.36—2016《食品安全国家标准食品氯化物的测定》中的气相色谱法进行比较,结果差异无统计学意义(P0.05)。结论该方法操作步骤简单快速,结果准确可靠,适用于实际白酒样品中氰化物的检测。     

罗丹明类柱前衍生剂HPLC-MS法检测果蔬中的单氰胺

合成了新型化学衍生试剂罗丹明B-N-羟基琥珀酰亚胺酯(RBS),基于RBS柱前衍生和高效液相色谱-质谱联用法建立了果蔬中单氰胺的检测方法。样品经乙酸乙酯萃取,用RBS衍生化后,采用高效液相色谱-质谱联用法测定。结果显示:衍生化试剂RBS具有很好的质谱检测灵敏度,对单氰胺的衍生化反应高效、专一。单氰胺浓度在0.005～5 mmol/L时呈现良好的线性关系,相关系数为0.9969,该方法的检出限为0.001 mmol/L,定量限为0.0025 mmol/L,样品加标回收率为77.56%～105.21%,相对标准偏差为1.88%～4.04%。该方法选择性好、灵敏度高、检测限低,可满足果蔬中的单氰胺残留量的测定。     

离子色谱法测定糖蜜样品中氯离子、硫酸根和硝酸根含量

目的 建立离子色谱法测定糖蜜样品中氯离子、硫酸根离子和硝酸根离子含量的方法。方法 使用去离子水对样品进行准确定容的稀释,之后对稀释后样品溶液过IC Na柱净化后上机测定样品的氯离子、硫酸根和硝酸根含量。使用Ion Pac _^TMAS19(4 mm × 50 mm)为分析柱,KOH淋洗液的浓度为35.0 mmol/L,流速1.0 mL/min,进样体积50 μL,外标法定量。结果 氯离子、硫酸根、和硝酸根标准溶液在0.05 ~ 2.0 mg/L浓度范围内呈现良好线性关系,R_²大于0.99,检出限0.02 ~0.1mg/L。在1.0 ~ 4.0 mg/L添加浓度上,回收率范围为85.4%~102.6%,相对标准偏差3.63%~10.64%。结论 该方法操作简便且快速准确,能够有效测定糖蜜中的氯离子、硫酸根和硝酸根含量,满足糖蜜中氯离子、硫酸根和硝酸根的检测需求以及样品的分析测定。     

毛细管电泳法测定婴幼儿食品中三嗪类农药残留量

采用毛细管电泳法对5种三嗪类农药进行了分离研究,考察了缓冲溶液的浓度、pH、胶束浓度和有机改性剂对分离的影响。以10mmol/L硼砂-50mmol/L十二烷基硫酸钠-10%(体积分数)甲醇溶液(pH9.42)为分离介质,压力进样方式,25kV恒压分离,221nm波长检测,各组分可达到基线分离。5种三嗪类农药标样在质量浓度0.1～10mg/L范围内呈良好线性关系,3个水平的加标回收率在81.6%～92.7%之间,方法最低检出限为0.1μg/g。     

反相离子对色谱法测定奶粉中核苷酸质量浓度

为检测奶粉中胞嘧啶核苷酸、尿嘧啶核苷酸、腺嘌呤核苷酸、鸟嘌呤核苷酸、次黄嘌呤核苷酸5种核苷酸的质量浓度,建立起奶粉中5种核苷酸的反相离子对色谱法。样品经质量分数为10%乙酸去除蛋白,在流动相为1.4 mmol/L四丁基硫酸氢胺含0.01 mol/L磷酸二氢钾(pH=4.0)∶甲醇=96∶4的条件下用C18色谱柱分离,紫外检测波长254 nm,流速1 mL/min,标准曲线法定量。5种核苷酸的平均回收率和样品重复测定变异系数分别是95.7%,96.0%,90.8%,98.7%,99.3%和0.583%,0.147%,0.257%,0.387%,0.167%。该方法无需进行固相萃取,快速灵敏,简便准确,适用于奶粉中核苷酸质量浓度的检测。     

酸奶中乳酸含量测定的毛细管区带电泳方法研究

建立了测定酸奶中乳酸含量的间接紫外检测毛细管区带电泳方法。在未涂渍的石英毛细管(内径75μm,有效长度50cm)中,以10.0mmol/L的2,6-吡啶二羧酸-0.5mmol/L十六烷基三甲基溴化铵(pH3.5)为运行电解质,检测波长214nm,在-15kV分离电压下酸奶中乳酸6min内能得到分析。方法重现性好,迁移时间和峰面积的相对标准偏差分别在1.0%和2.0%以内。在相应的浓度范围内,峰面积与样品浓度之间呈现良好的线性关系。该法简单、快速、灵敏度高,为测定酸奶中乳酸含量提供了一种高效、快速、简便的方法。     

高效液相色谱-串联质谱法测定双壳类水产品麻痹性贝类毒素

目的采用Supelco ENVI-Carb柱净化双壳类水产品中的麻痹性贝类毒素(PSP),建立高效液相色谱-串联质谱(HPLC-MS/MS)法检测双壳类水产品中的PSP,为水产品中的PSP检测提供方法依据。方法选用色谱柱TSK-GEL Amide-80(2.0 mm×250 mm,5μm),以2 mmol/L甲酸铵-50 mmol/L甲酸水和95%乙腈水(含2 mmol/L甲酸铵-50 mmol/L甲酸)为流动相,采用梯度洗脱进行分离。样品用1%乙酸溶液进行提取,上清液加入氨水后(pH=4.0)经Supelco ENVI-Carb柱净化,将洗脱液抽干收集,上机测定。多重反应监测(MRM)模式检测。结果PSP的线性范围为8.1~705.0μg/kg,检出限为10~35μg/kg,回收率在47.0%~91.3%之间。结论本方法提取效果好、基质效应小,适用于双壳类水产品中麻痹性贝类毒素的痕量检测。     

离子色谱法检测熟肉制品中亚硝酸盐含量的影响因素分析

目的:探讨离子色谱法检测熟肉制品中亚硝酸盐含量的影响因素。方法:样品提取净化后,用离子色谱法测定,对峰面积进行定量。结果:样品提取条件为40℃超声提取30 min,色谱检测条件是4.5 mmol/L Na2CO3+0.8 mmol/L Na HCO3缓冲液,流速为1.2 m L/min,进样体积为50μL,相关系数0.9932,线性范围0.1~20 mg/L,检出限0.02 mg/L,回收率在97%~99%之间,相对标准偏差RSD小于5%。结论:所测结果准确可靠,灵敏度高,重现性好,适用于熟肉制品中亚硝酸盐含量的检测。     

基于MnO2纳米片类氧化酶特性的有机磷农药荧光分析方法建立

利用MnO2纳米片类氧化酶特性并结合有机磷农药的酶抑制原理,构建一种快速、简便、高灵敏有机磷农药荧光分析方法。通过测定反应体系荧光强度前后的变化,可以检测样品中有机磷农药的含量。通过优化酶浓度、底物浓度和反应时间,发现乙酰胆碱酯酶浓度为9.375 U/L,底物浓度为10 mmol/L,反应时间为11 min时,该荧光分析方法检测性能最佳,对氧磷的动态检测范围为1.56～200 ng/mL,检出限达到0.5 ng/mL（RSN=3）,运用该方法测定标准添加的自来水、卷心菜、燕麦样品的回收率在83.4%～105.9%之间,表明该方法具有很高的灵敏度与准确性,为快速高灵敏测定有机磷农药提供一种新的可能。     

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