肉类食品中肠炎沙门氏菌快速检验即用型质控样品研制

针对肉类食品中肠炎沙门氏菌的检测,研制出基质辅助激光解吸电离飞行时间质谱（matrix-assisted laser desorption ionization time-of-flight mass spectrometry,MALDI-TOF-MS）即用型质控样品,通过培养计数和MALDITOF-MS检测及统计分析的方式验证质控样品的均匀性和稳定性。结果表明：研制的肠炎沙门氏菌质控样品为白色小球,均匀性验证实验中,质控样品培养计数结果F=0.75,小于临界值,表明均匀性一致;运输稳定性实验表明,质控样品在37、25℃环境下活菌数量稳定,生长良好;贮藏稳定性实验表明,质控样品在-20℃条件下贮藏28 d的复苏率为90.6%,在4℃条件下贮藏28 d的复苏率为89.0%,说明样品性质稳定,能够长期稳定保存;对每次MALDI-TOF-MS检测结果进行分析同样表明检测结果稳定。综上所述,本研究研制出的肠炎沙门氏菌快速检验即用型质控样品均匀性和稳定性良好,可作为阳性质控样品用于肠炎沙门氏菌检测和质量控制。     

猪肉中氯霉素质控样品的制备及其应用

目的：以猪肉为代表基质制备氯霉素质控样品,并探究其在快速检测方面的应用。方法：称取适量新鲜猪肉,加入一定体积的氯霉素标准溶液,经绞碎匀浆、真空冷冻干燥、粉碎、过筛、包装等步骤制得质控样品。依据CNAS-GL003:2018《能力验证样品均匀性和稳定性评价指南》对质控样品进行均匀性与稳定性评价。结果：均匀性检验结果显示制备的低、高浓度氯霉素质控样品的F值均小于F0.05(9, 10),样品间不存在显著性差异,表明均匀性良好。稳定性检验结果显示各时间段的t值均少于t临界值,表明样品在8个月存储期间的稳定性良好。结论：通过该方法制得的质控样品可适用于日常快检工作的质量控制、产品验证、盲样考核等领域,且制备方式具有可复制性。     

肉类食品中大肠杆菌快速检验即用型质控样品研制

为实现肉类食品中大肠杆菌快速检验,研制出大肠杆菌基质辅助激光解吸电离飞行时间质谱（matrix assisted laser desorption/ionization time-of-flight mass spectrometry,MALDI-TOF-MS）检验即用型质控样品,可以直接溶解使用,无需再次培养,并系统分析了质控样品的均匀性和稳定性。结果表明：经筛选得到冻干基质最佳条件,质控样品存活率均在90%以上;质控样品培养计数结果F=0.567,小于临界值,证明均匀性好;质控样品在37℃和25℃环境下放置14 d后菌株计数稳定,在-20℃和4℃环境下贮藏28 d复苏率分别为101.5%和99.6%,在37℃和-20℃环境下贮藏28 d后的MALDI-TOF-MS检测结果仍保持一致,表明样品稳定性好,满足作为质控样品的要求。     

食品检测用鼠伤寒沙门氏菌标准物质的研制

目的 研制均匀稳定的鼠伤寒沙门氏菌标准物质。方法 采用冷冻干燥技术制备含量为1.5-2.0×103 CFU /样品的菌球, 参照CNAS—GL29: 2010《标准物质/标准样品定值的一般原则和统计方法》, 随机抽取22件样品进行均匀性检验, 采用单因素方差分析对结果进行统计分析, 将样品分别于-20、4、25、37 ℃条件下保藏, 对其储藏稳定性和运输稳定性进行评价, 并组织3家实验室进行协同标定, 再使用45件食品作为基质, 按照国标法检验鼠伤寒沙门氏菌标准物质的适用性。结果 对22件标准物质的均匀性检测结果进行单因素方差分析, F=1.986, 符合标准物质的要求。标准物质在?20 ℃保藏28 d, 复苏率为103.1%; 在4 ℃保藏28 d, 复苏率为102.0%; 在25 ℃保藏14 d或者37℃保藏7 d, 样品中菌含量仍保持在103 CFU/样品的水平, 说明样品的短期储藏稳定性、长期储藏稳定性和运输稳定性都符合要求。经3家实验室协同标定, 样品活菌含量均在103 CFU/样品水平, 生化鉴定结果均符合沙门氏菌的特征; 标准物质加入到45种食品基质中, 均可以检出沙门氏菌。结论 本研究所制备的鼠伤寒沙门氏菌标准物质的均匀性、储藏稳定性和运输稳定性均符合要求, 适用性良好, 可用于食品检测实验室的质量控制和食品中沙门氏菌检测结果的评价。     

乳酸菌微胶囊制剂的功能性与稳定性研究

乳酸菌微胶囊制剂调节肠道菌群功能的试验结果表明,在1g·kg~(-1)·d~(-1)的剂量下,小鼠实验前后粪便中双歧杆菌和乳杆菌明显增加,产气荚膜梭菌不增加,肠杆菌、肠球菌无明显变化,说明乳酸菌微胶囊制剂对小鼠具有调节肠道菌群的功能。乳酸菌微胶囊制剂和未经包埋的乳酸菌全蛋液冻干粉置于不同温度下(4℃和-20℃)储藏,分别测定其初始和1年后乳酸菌活性。结果表明,乳酸菌微胶囊制剂的储藏稳定性优于全蛋液冻干粉,两种菌剂在-20℃条件下的储藏稳定性均优于在4℃条件下的储藏稳定性,在4℃条件下乳酸菌微胶囊制剂活菌数的下降很可能会影响其功能性,因此,在-20℃条件下储藏更利于乳酸菌微胶囊制剂长期保持稳定。     

瓷珠保存法定量制备单核细胞增生李斯特菌质控菌株

为了获得食品微生物实验室操作方便、使用便捷的菌种保存方式,利用瓷珠保存法制备单核细胞增生李斯特菌质控样品。通过室内复现性检测、储藏稳定性及活力的检验证明,此法制备的质控样品具有均匀性、储藏稳定性,能满足质控样品使用的要求,可以用于食品微生物日常检验工作中的阳性对照试验。     

氨基甲酸酯类农药残留质控样品的制备与评价-以灭多威为例

目的 建立一种蔬菜冻干粉中氨基甲酸酯类农药残留质控样品的制备方法并对制备技术进行评价。方法 以圆白菜为基质, 灭多威为目标物, 采用真空冷冻干燥, 基质添加的方式制备质控样品。采用液相色谱-串联质谱法对质控样品中目标物含量进行测定。通过随机抽样测定以评估样品的均匀性, 通过观察样品12个月内目标物检测结果变化以评估样品的稳定性。结果 本方法制备的灭多威质控样品均匀性和稳定性良好。蔬菜冻干粉质控样品便于贮藏、运输且在常温下能够长期稳定保存。样品中灭多威的制备值与测得值较好吻合。结论 本研究确立了蔬菜冻干粉中灭多威质控样品的制备方法, 所建立的制备技术可以确保质控样品定值结果的准确性, 为氨基甲酸酯类农药残留质控样品制备方法的开发提供技术支持。     

食品中副溶血性弧菌检验能力验证样品的研制及其应用

目的研制食品中副溶血性弧菌检验能力验证样品,并应用于副溶血性弧菌能力验证试验中。方法能力验证样品包括0～3瓶阳性样品和0～3瓶阴性样品。阴性样品仅含有背景细菌,阳性样本在背景菌的基础上添加有副溶血性弧菌。为防止数据串通,编制1～180的随机数字表,其中90个随机数字作为阳性样品编码,另外90个随机数字则用为阴性样品编码。随机抽取冻干质控阳性样品、阴性样品各20瓶,参照本次能力验证推荐的GB4789.7-2013对样品进行均匀性检验,阳性样品均需要检出副溶血性弧菌,而阴性对照样品应不得检出副溶血性弧菌。将副溶血性弧菌能力验证样品分别在?30、4℃储藏30d监测其储藏稳定性,同时在25和37℃下储藏7 d监测其运输稳定性。结果副溶血性弧菌的质控样在均匀性、储藏稳定性和运输稳定性均能满足质控样使用的要求。在39家实验室反馈结果中,36家结果评定为满意,满意率为92.3%。结论食品中副溶血性弧菌能力验证样品可以满足此次能力验证的需求,国内实验室大部分能满足考核要求,仍有部分实验室需要提高检验检测能力。     

2018—2020年度乳粉中克罗诺杆菌属(阪崎肠杆菌)能力验证样品的研制及其应用

目的 制备乳粉中克罗诺杆菌属(阪崎肠杆菌)检验能力验证样品,并应用于2018—2020年度实验室能力验证考核。方法 将背景菌株和克罗诺杆菌属通过生化、基质辅助激光解吸电离飞行时间质谱鉴定确认菌株种属。采用冷冻干燥技术制备的阴性样品(含背景菌)和阳性样品(含背景菌和克罗诺杆菌属)。随机抽取阳性样品和阴性样品各20份进行均匀性检验,然后将样品分别存放于-20℃和4℃进行储藏稳定性检验,存放于25℃和37℃进行运输稳定性检验。向参加考核的实验室发放样品并提供作业指导书,回收各实验室结果进行统计。结果 菌株种属鉴定结果与预期结果一致,均匀性、储藏稳定性和运输稳定性均满足要求。2018—2020年度考核结果满意率分别为97.1%、94.7%和100%。结论 制备的样品满足此能力验证项目的需求,通过组织能力验证考核可以反映出我国实验室之间差异,有助于进一步提高实验室检验水平。     

食品检测用大肠埃希氏菌标准物质的研制

目的建立食品检测用大肠埃希氏菌标准物质的制备方法, 研制均匀稳定的标准物质,用于实验室内部质量控制。方法采用冷冻干燥技术制备含量为4-5×104CFU/样品的菌球,参照《CNAS-GL29：2010标准物质/标准样品定值的一般原则和统计方法》,随机抽取20件样品进行均匀性检验,采用单因素方差分析对结果进行统计分析;将样品分别于-20℃、4℃、25℃条件下保藏,对其储藏稳定性和运输稳定性进行评价。并组织3家实验室进行协同标定,再使用20件食品作为基质,按照国标法检验大肠埃希氏菌标准物质的适用性。结果对20瓶标准物质的均匀性检测结果进行单因子方差分析： F=1.933, 符合标准物质的要求。标准物质在?20 ℃保藏28 d,复苏率为96.2%;在4 ℃保藏14 d,复苏率为77.0%;25 ℃保藏7 d,样品中菌含量仍保持在104CFU/样品的水平,说明样品的短期储藏稳定性、长期储藏稳定性和运输稳定性都符合要求。经3家实验室协同标定, 样品活菌含量均在104CFU/样品水平,生化鉴定结果均符合大肠埃希氏菌的特征;标准物质加入到20种食品基质中, 均可以检出大肠埃希氏菌,活菌含量仍保持在104CFU/样品的水平。结论本研究所制备的大肠埃希氏菌标准物质的均匀性、储藏稳定性和运输稳定性均符合要求,适用性良好,可用于食品检测实验室的质量控制和食品中大肠埃希氏菌检测结果的评价。     

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