巧克力中沙门氏菌能力验证结果与分析

目的 分析实验室对巧克力中沙门氏菌检测能力验证实验与结果。方法 依据GB 4789.4-2016《食品安全国家标准 食品微生物学检验 沙门氏菌检验》对巧克力样品进行沙门氏菌检测。参照能力验证计划参试指导书来进行测定和结果判断。结果 通过平板法结合生化鉴定实验结果可知, 编号CODE:384有可疑目标菌落检出沙门氏菌阳性菌, CODE:544、CODE:699的可疑目标菌落均未检出沙门氏菌阳性菌。结论 本次实验室对巧克力中沙门氏菌检测能力验证结果合格, 为提高相关微生物实验室的检测能力提供参考。     

巧克力中沙门氏菌检验能力验证的结果与分析

目的 参加由中国食品药品检定研究院负责实施的NIFDC-PT-135巧克力中沙门氏菌检验能力验证活动, 提高微生物实验室沙门氏菌的检验检测能力,对实验室进行质量控制。方法 按照NIFDC-PT-135《巧克力中沙门氏菌检验作业指导书》和GB 4789.10-2016《食品安全国家标准 食品微生物学检验 沙门氏菌检验》条目要求对3件样品进行检验, 利用沙门氏菌生化鉴定盒和API20E生化鉴定试剂条进行鉴定。结果 样品编号为CODE: 0024的样品未检出沙门氏菌, 编号为CODE: 0754的样品检出沙门氏菌, 编号为CODE: 0883的样品未检出沙门氏菌。结论 本次实验室的能力验证试验结果为“满意”, 通过参加沙门氏菌的能力验证, 促进检测技术水平的提升, 为以后的工作开展提供技术储备。     

食品能力验证中沙门氏菌的分离鉴定与血清分型

目的参加沙门氏菌分离鉴定与血清分型的能力验证,以加强实验室整体水平与能力。方法参照GB4789.4-2010《食品安全国家标准食品微生物学沙门氏菌检验》进行沙门氏菌检测,将生化试验与VITEK2鉴定结果符合沙门氏菌编号的样品进行血清学试验。结果编号CODE 1样品检出巴尔多沙门氏菌,CODE 3样品检出鼠伤寒沙门氏菌,其余8个样品均未检出沙门氏菌。本实验室顺利完成能力验证实验,与组织方结果一致,结果为满意。结论参加能力验证是提高检验机构内部质量控制最有效的手段之一,可有效提高检验机构出具检验数据的可靠性和有效性,确保实验室持续维持较高的检验水平。     

食品中沙门氏菌能力验证

目的:提升食品检测机构的检测能力,同时结合本次能力验证实验,总结食品中沙门氏菌检测过程中的关键控制要素,寻找操作中的问题,讨论控制措施。方法:依据我国食品药品检验研究院下发的能力验证作业指导书、国家标准《食品安全国家标准食品微生物学检验沙门氏菌检验》GB 4789.4-2016要求的检验方法对编号为CODE0477、CODE0884、CODE0861的3份巧克力样品中的沙门氏菌进行增菌、分离、生化、血清学鉴定。结果:CODE0477、CODE0884未检出沙门氏菌,CODE0861结果为检出沙门氏菌,3份检测样品的检测结果评价均为满意。结论:通过能力验证实验可提升检验检测水平,同时也为处理细菌性食物中毒原因奠定了基础。     

巧克力中沙门氏菌检验能力验证研究

目的 对参加中国食品药品检定研究院组织的NIFDC-PT-135巧克力中沙门氏菌检验能力验证进行分析。方法 在参照GB 4789.4-2016《食品国家安全标准 食品微生物学检验 沙门氏菌检验》和能力验证作业指导书传统方法鉴定的基础上, 借助miniVIDAS和VITEK2 2种仪器进行检验分析。结果 CODE0002未检出沙门氏菌、CODE0485检出肠沙门菌双相亚利桑那亚种, CODE0633检出鼠伤寒沙门氏菌。结论 本次能力验证实验结果为满意。实验室在进行沙门氏菌检验时可以使用仪器与传统分析方法相结合的检验方法, 但是要注意一些细节问题, 防止漏检和误检。     

2018年巧克力中沙门氏菌检测能力验证结果与分析

目的参加中国食品药品检定研究院组织的NIFDC-PT-135巧克力中沙门氏菌检验能力验证,提高实验室的检测技术能力与水平。方法按照盲样作业指导书的要求对样品进行前处理后,依据GB4789.4-2016《食品安全国家标准食品微生物学检验沙门氏菌检验》中的方法,对3份样品进行沙门氏菌的分离和血清学鉴定,对分离出的可疑菌落用全自动微生物鉴定系统进行鉴定。结果CODE0109样品中检出鼠伤寒沙门氏菌、CODE0143样品中检出肠沙门双相亚利桑那亚种(沙门氏菌Ⅲb),CODE0835样品中未检出沙门氏菌。本实验室顺利完成考核,测定结果与考核结果一致。结论本次能力验证检出的肠沙门双相亚利桑那亚种在沙门氏菌显色平板上出现蓝色菌落,而以往则为紫红色菌落,因此在检测中应引起重视。通过此次能力验证,本实验室的沙门氏菌检测技术水平得到了有效验证和提高。     

食品中沙门氏菌检出能力验证结果与分析

目的为了提升实验室的食品中沙门氏菌检测能力,增强实验室竞争能力,本实验室参加了中国食品药品检定研究院组织的NIFDC-PT-010食品中沙门氏菌检出能力验证。方法利用全自动免疫检测系统(VIDAS)对能力验证中的5个样品进行快速筛查,依据GB4789.4-2010沙门氏菌检验进行血清学试验,采用16S r DNA全序列分析、全自动微生物生化鉴定系统(VITEK2)和全自动微生物基因指纹鉴定系统(Ribo Printer)对分离出的疑似菌进行鉴定。结果编号为CODE 1的样品检出阿贡纳沙门氏菌和婴儿沙门氏菌,CODE 3检出蒙得维的亚沙门氏菌,CODE 5检出鼠伤寒沙门氏菌,CODE 2和CODE 4未检出。结论 5个样品测试均取得优秀的结果。     

能力验证中沙门氏菌的分离鉴定与血清分型

目的通过参加NIFDC-PT-098乳粉中沙门氏菌检验的能力验证,提高本实验室的检测能力,增强实验室竞争力。方法依据GB 4789.4-2016《食品安全国家标准食品微生物学检验沙门氏菌检验》中的方法,对2份样品中的沙门氏菌进行分离和血清学鉴定。并以全自动荧光免疫分析系统(MINI VIDAS)进行快速初筛,利用全自动微生物生化鉴定系统(VITEK2)对分离出的疑似菌进行生化鉴定。结果编号CODE423检出鼠伤寒沙门氏菌,其血清分型为O:4,5,12,H:I;1,2。编号CODE484未检出。结论本次能力验证获得满意结果,发现以国标法为基准,优先选用沙门氏菌属显色培养基平板和XLD平板为参照,同时使用VITEK2和MINI VIDAS作为辅助进行检测,综合这几种方法可确保实验结果的准确性,这为以后检验使用辅助方法检测提供了参考依据。同时本次能力验证也促进了实验室保持较高的检验水平。     

食品能力验证中沙门氏菌的分离和鉴定

目的为了提升实验室食品中沙门氏菌检测能力,增强实验室竞争能力,本实验室参加了中国食品药品检定研究院组织的沙门氏菌检测能力验证活动。方法依据中华人民共和国国家标准GB 4789.4-2010,采用传统分离方法和血清学鉴定,联合全自动微生物生化鉴定系统(VITEK2-compact)对分离出的疑似菌进行生化鉴定。结果编号为CODE1样品+CODE1奶粉混合样检出纽波特沙门氏菌和科林德尔沙门氏菌,CODE3样品+CODE3奶粉混合样检出维普拉沙门氏菌、鼠伤寒沙门氏菌和埃科沙门氏菌,其余8个样品未检出。结论顺利完成本次能力验证活动。     

巧克力中沙门氏菌检验能力验证的分析

目的分析参加中国食品药品检定研究院组织的NIFDC-PT-135巧克力中沙门氏菌检验能力验证实验结果。方法巧克力样品的前处理按照作业指导书要求进行,沙门氏菌的分离及鉴定按照GB4789.4-2016《食品安全国家标准食品微生物检验沙门氏菌检验》进行,传统生化试验结合VITEK 2鉴定结果进行综合判定。结果 CODE0559样品中检出沙门氏菌属,CODE0205样品中检出肠沙门氏菌双相亚利桑那亚种,CODE0863样品中未检出沙门氏菌, 3个样品能力验证结果均与组织方一致。结论基于国标法检测沙门氏菌时,应综合使用几种分离平板,传统生化试验并结合VITEK2作为辅助检测,以确保检测结果的准确性。     

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.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

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.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.