沙门氏菌能力验证样品制备

目的研究制备适用于沙门氏菌(Salmonella)能力验证(PT)检测项目的冷冻干燥样品,通过能力验证确定实验室或检查机构的校准、检测能力。方法对目标菌与干扰菌进行10倍梯度稀释,对不同稀释度的菌液进行菌落计数并计算菌浓度,确定沙门氏菌与干扰菌的添加量,以冻干的绿豆粉为基质,脱脂奶粉为冻干保护剂,将细菌混合物与冻干保护剂混合均匀,采用真空冷冻干燥方式分别制备沙门氏菌能力验证阳性样品与阴性样品,采用西林瓶真空包装、4℃冷藏贮存;通过随机抽样和鉴定以评估样品的均匀性,通过观察样品在90 d内不同温度下目标菌的测试结果以评估样品的稳定性。结果每个样品最终添加10~100 CFU目标菌,添加104 CFU干扰菌;抽检的样品均能有效鉴定,显示PT样品具有较好的均匀性;通过保存温度和时间的稳定性检验显示测试结果符合预期效果,PT样品具有较好的稳定性。结论建立了有效的沙门氏菌能力验证样品制备的方法与评价程序。     

单核细胞增生李斯特氏菌能力验证样品的 制备与验证

目的研究制备适用于验证、评价实验室或检测机构检测能力的单核细胞增生李斯特氏菌(Listeria monocytogenes,LM)的能力验证冷冻干燥样品。方法对目标菌与干扰菌进行10倍梯度稀释,对不同稀释度的菌液进行菌落计数得到菌含量,确定单核细胞增生李斯特氏菌与干扰菌的添加量;对保护剂和预冻条件进行筛选优化,制备单核细胞增生李斯特氏菌能力验证样品。冻干样品采用西林瓶真空包装,4℃条件下冷藏保存,随机取样检测评估样品均匀性,并在210 d期间内定期抽样检测不同贮存温度下的冻干样品,检测评估样品的稳定性。结果每个冷冻干燥阳性样品最终添加目标菌单增李斯特菌和干扰菌分别为10~2 CFU/m L和10~4 CFU/m L;每个阴性样品添加干扰菌10~4 CFU/m L;最佳冻干保护剂的组合为海藻糖3%,脱脂奶粉8%,谷氨酸钠1.5%。检测结果显示PT冻干样品具有较好的均匀性和稳定性。结论建立的单核细胞增生李斯特氏菌能力验证样品制备方法与评估程序均为有效,适用于验证与评价实验室或检查机构检测能力,满足能力验证活动的要求。     

European standardization of methods for pesticide residue analysis in foods?current status

The aim of this paper is to inform all scientists working in pesticide residue analysis on the contents, size and background of European standards (ENs) in this area. These ENs were established by a Technical Committee (TC 275) of the European Committee for Standardization (CEN) and each CEN member country is obliged to implement them as national standards. EN 1528:1996 comprises eight methods for the multiresidue determination of organochlorine pesticides and polychlorinated biphenyls (PCBs) in fatty foods. For non-fatty foods such as fruits and vegetables, EN 12 393:1998 provides five multi-residue methods. In addition, three methods for dithiocarbamate fungicides in EN 12 396: 1998/2000 and two methods for bromide residues in EN 13 191:2000 are already available. In this way, a valuable harmonization of methods across Europe is achieved which is useful for quality control in the food industry as well as in official food inspection.     

农药残留检测技术的研究进展

生产食糖的原料——甜菜，在生长期间会受到多种病虫害的危害。为了消灭病虫害，在甜菜生长期间，有时要使用多种杀菌剂、杀虫剂、除草剂等化学农药。国家《食糖卫生标准》（13104—2005）已于2005年1月25日由中华人民共和国卫生部、中国国家标准化管理委员会发布，2005年10月1日实施。标准提出了对制糖原料甘蔗、甜菜进行农药残留检测的要求，这对于保障人民身体健康，有效地控制农药在甜菜生产中的合理使用和对其残留量进行监控是十分必要的。[第一段]     

Evaluation of cost-effective methods in the pesticide residue analysis of non-fatty baby foods

Three non-fatty ready-to-eat baby food matrices (fruits: juice, purée and cocktail plus rice flour/starch and sugar) were fortified with 0.01, 0.05, 0.1 and 0.2 mg/kg of dimethoate, chlorpyrifos, methidathion, phosalone and diazinon. Simple methods including extraction by ethyl acetate [EtAc] and acetone partition and determination by gas chromatography with Nitrogen–Phosphorus Detector (GC–NPD) were used. Acceptable pesticides recoveries (70–110%), low detection and quantification limits (0.001 to >0.1 mg/kg and 0.005 to 0.04 mg/kg, respectively) and repeatabilities (%RSDs), in 0.01 mg/kg, within 2.9–13.9% were observed. However, analytes recoveries were affected (p < 0.05) by both the baby food formulation and the extraction method used. Specifically, fruits purée and cocktail EtAc extracts gave excessively over-(dimethoate recoveries of 119.7–153.5%) or underestimation (phosalone and especially diazinon recoveries of 19.3–79.2%) in contrast to fruits juice (e.g., 61.3–87.9%). Also, EtAc extracts showed higher amount of lipophilic compounds and provided lower recoveries for non-polar analytes than those of acetone partition. Consequently, the examined methods may be successfully applied in non-fatty baby foods with the matrix-matched standards determination, following improvements of certain parameters in relation to the clean-up of samples.     

大豆粉转基因成分能力验证样品的检测分析

目的 提高实验室对转基因大豆定性检测的准确性和检测人员专业技术水平, 增强实验室竞争力。方法 通过核酸蛋白仪器分析法和单重实时荧光PCR (simplex real-time fluorescence PCR)法对样品内源基因扩增的循环阈值的影响来比较2种方法, 分析2种DNA提取试剂盒的提取质量。对标准SN/T 1204-2016《植物及其加工产品中转基因成分实时荧光PCR定性检验方法》扩增反应体系中DNA模板量进行优化后, 对样品进行检测。再依据标准SN/T 1202-2010《食品中转基因植物成分定性PCR检测方法》的要求, 对样品进行检测。最后对2个标准的检测结果进行比对。结果 通过内源基因扩增循环阈值的数据确认, 更能准确反映试剂盒提取的DNA是否满足后续外源基因的分析检测要求。2种标准方法对19-N578和19-M913 2个待测样品的检测显示3种外源基因CaMV35S、NOS、CP4-EPSPS均为阴性, 19-N578和19-M913待测样品均为非转基因大豆。结论 本次能力验证获得满意评价。DNA提取质量的评估, 体系中DNA模板量的优化, 检测方法的选择和实验的质量控制都是影响能力验证结果的重要因素。     

Study on rapid analysis method of pesticide contamination in processed foods by GC-MS and GC-FPD

A simple and rapid method using GC-MS and GC-FPD for the determination of pesticide contamination in processed food has been developed. Pesticides were extracted from a sample with ethyl acetate in the presence of anhydrous sodium sulfate, then cleaned up with a combination of mini-columns, such as macroporous diatomaceous earth, C18, GCB (graphite carbon black) and PSA. Recovery tests of 57 pesticides (known to be toxic or harmful) from ten kinds of processed foods (butter, cheese, corned beef, dried shrimp, frozen Chinese dumplings, grilled eels, instant noodles, kimchi, retort-packed curry and wine) were performed, and the recovery rates were mostly between 70% and 120%. This method can be used to judge whether or not processed foods are contaminated with pesticides at potentially harmful levels.     

农药残留检测实验室标准物质的管理

实验室的农药残留检测用标准物质对实验室农产品的农药残留检测工作具有重大的意义。农药残留检测用标准物质大部分为剧毒化学品,管理不当有可能会引发公共安全事故,所以建立健全剧毒化学品管理制度,加强宣贯培训,才能有效地指导实验室使用人员规范使用剧毒化学品,确保农药残留检测用标准物质的规范管理,保证安全生产和实验室检验检测工作的顺利进行。本文主要阐述了农药残留实验室的标准物质从采购、验收与入库、储存、领用、期间核查、废弃处置等环节的管理要点,以及国家对剧毒化学品管理的相关规定,以通过标准物质的规范化、法制化、科学化管理,来保证农药残留标准物质的正确使用、质量控制与溯源,确保实验室标准物质的安全管理。     

食品农药污染综合监管模式的探索与思考

为保障食品安全，金山区通过建立以块为主，条块结合的食品安全监管机制、蔬菜农药残留监测机制、从农田到餐桌的全程监管体系，加强宣传教育工作，探索建立了食品农药污染的综合监管模式，取得了初步成效并提出了实施中应当注意把握的难点问题。     

食品中有机磷农残测定能力验证结果的再利用

目的评估嘉兴市食品检验机构实验室的能力水平,实现能力验证结果的再利用。方法实施"食品中有机磷农药残留量(敌敌畏)测定"能力验证,通过稳健统计技术对测试结果进行判定,对影响能力验证评价结果的因素进行分析。结果有12个实验室检测结果为满意,占92.3%。结论本次能力验证研究客观评价了实验室有机磷农药残留量检测的能力,提供了全面深入的技术分析,帮助实验室查找原因,采取措施,提高检测能力。     

Nondestructive testing methods for pesticide residue in food commodities: A review

Pesticides play an important role in increasing the overall yield and productivity of agricultural foods by controlling pests, insects, and numerous plant-related diseases. However, the overuse of pesticides has resulted in pesticide contamination of food products and water bodies, as well as disruption of ecological and environmental systems. Global health authorities have set limits for pesticide residues in individual food products to ensure the availability of safe foods in the supply system and to assist farmers in developing the best agronomic practices for crop production. Therefore, the use of nondestructive testing (NDT) methods for pesticide residue detection is gaining interest in the food supply chain. The NDT techniques have several advantages, such as simultaneous measurement of chemical and physical characteristics of food without destroying the product. Although numerous studies have been conducted on NDT for pesticide residue in agro-food products, there are still challenges in real-time implementation. Further study on NDT methods is needed to establish their potential for supplementing existing methods, identifying mixed pesticides, and performing volumetric quantification (not surface accumulation alone).     

免疫分析技术在有机磷农药残留检测中的应用

介绍了有机磷农药的危害及常用的几种检测方法,对免疫分析技术在有机磷农药残留检测方面的应用进行了归纳分析.着重介绍了研究最多的酶联免疫分析法,对影响免疫分析方法的几个关键因素进行了综述,并探讨了免疫分析技术在有机磷农药检测领域应用的进展.     

免疫分析技术在有机磷农药残留检测中应用

该文简介有机磷农药危害及常用几种检测方法,对免疫分析技术在有机磷农药残留检测中应用进行归纳分析;着重介绍研究最多的酶联免疫分析法,对影响免疫分析方法几个关键因素进行综述,并探讨免疫分析技术在有机磷农药检测领域发展。     

分散液液微萃取技术在农药残留分析中的应用概述

目前农药残留问题已成为全社会关注的热点,发展快速、可靠和环境友好的农药残留前处理检测技术,对于合理使用农药、保护环境和保障人类健康具有重要意义。分散液液微萃取(dispersive liquid-liquid microextraction,DLLME)是2006年发展起来的一种新型的液液微萃取技术,具有操作简单、富集倍数高、有机溶剂用量少等特点,目前已广泛应用于农药残留的检测中。本文对分散液液微萃取在水、蔬菜水果、牛奶、酒、蜂蜜、谷物、茶叶、中药材、土壤、生物样本中农药残留检测的应用进行了综述,并对该方法的前景进行了展望。     

大肠埃希氏菌O157和O111能力验证样品的研制

目的研制植物源性成分绿豆基质中O157和O111检测能力验证样品,建立有效的样品制备流程来考核实验室检测致泻大肠埃希氏菌O157和O111的能力,根据参加实验室检测结果是否准确及可靠来评价实验室检测水平,并促进实验室检测体系进一步完善。方法选用O157和O111的ATCC标准菌株制备样品,以绿豆粉为基质,真空冷冻干燥技术制备样品。采用显色培养基、荧光定量PCR、全自动细菌生化鉴定仪、VIDAS全自动免疫荧光分析仪和血清型鉴定进行定性检测,并进行菌落计数。结果随机选取每一批阳性样品中的30个样品,每个样品中目标菌数在21~60 CFU之间,并且A组与B组阳性样品中均检测出目标菌,而阴性样品中均没有出现目标菌。结论表明采用本方法制备的能力验证样品均一稳定,能较好地评价实验室致泻大肠埃希氏菌O157和O111的检测能力。     

蒸谷晚籼米的制备及其无机元素和农药残留分析

对蒸谷晚籼米加工工艺中的浸泡、汽蒸、干燥三个重要环节进行了实验,并对蒸谷晚籼米中重要无机元素含量和有机磷农药残留进行了分析。实验结果表明,蒸谷晚籼米制备过程中浸泡、汽蒸和干燥的工艺条件为:在70℃水中浸泡2.5h,于100℃下汽蒸30min,先在110℃下干燥3h后,再在60℃下干燥4h。在此条件下生产的蒸谷晚籼米爆腰率为7.6%,远低于普通白米加工的爆腰率;蒸谷后晚籼米总灰分含量比未蒸谷前增加了34.5%,其中Ca、Fe、Zn等重要无机元素的含量明显增加;此外蒸谷晚籼米中未检出有机磷农药,说明蒸谷晚籼米食用安全性高。     

乳粉中沙门氏菌能力验证样品研制及应用评价

目的 研制均一性和稳定性符合能力验证要求的沙门氏菌能力验证样品,并应用于乳粉中沙门氏菌检测的能力验证.方法 选取本实验室保存的ATCC、CMCC标准菌株及食品中分离菌株作为能力验证样品的菌株来源,采用基质辅助激光解吸电离飞行时间质谱和全自动微生物分析系统进行种属确认,并对沙门氏菌标准菌株进行血清学分型;采用冷冻干燥技术...