检测霜霉威的两种方法的比较

目的比较胶体金法与液相色谱-质谱质谱联用法(LC-MS/MS)在霜霉威检测中的应用。证实胶体金试纸检测蔬菜中霜霉威残留的可靠性,并以此为基础建立一个新的检测手段。方法通过胶体金试纸条半定量方法检测的试样,再用液/质谱法联用定量检测试样中的霜霉威。结果胶体金试纸检测为阴性的100个试样,经液/质谱法联用检测结果为未检出,符合率为100%。添加霜霉威的胶体金试纸检测阳性的试样经液/质谱法联用检测,符合率为100%,添加的Cutoff值样品回收率达到93%。结论与液/质联用检测法相比较,胶体金法检测霜霉威具有操作简便、观察直观、快速、省时的特点,特异性强、敏感性较高,从而为检测霜霉威提供了一种快速的检测方法。     

乳品中多种抗生素残留胶体金检测方法研究

研究用于牛奶和奶粉中多种抗生素残留同时检测的胶体金免疫层析试纸条。基于胶体金免疫层析技术,搭建抗原包被体系和胶体金标记抗体体系,优化检测方法,考察胶体金快速检测试纸条的检测灵敏度、特异性、准确度和实际样本适应性。试纸条可同时检测卡那霉素、红霉素、林可霉素3种药物在牛奶、奶粉中的残留,检测限分别为50.0,20.0和75.0μg/L,假阳性率和假阴性率均为0,样本无需前处理,检测操作简单,10 min内实现3种药物同时检测。采用胶体金试纸条和液相色谱串联质谱法对20份牛奶和奶粉盲样进行比对试验,阳性样品全部检出,2种方法测定结果一致。建立的胶体金免疫层析技术及试纸条检测准确可靠,适用于现场大批量样本的快速检测和筛选。     

酶联免疫快速检测方法在食品安全中的应用

免疫学技术通过抗原和抗体的特异性结合反应,再辅以免疫放大技术来鉴别要检测的物质。免疫方法的优点是样品在进行现场检测,可采用免疫技术进行筛选。由于免疫学方法具有高灵敏、高特异性、快速等优点,所以近年来,该方法在食品安全检测上也应用广泛,本文主要从酶联免疫吸附法（ELISA）、化学发光法、胶体金试纸条这几种方法在食品安全检测中的应用进行介绍。     

新霉素半定量胶体金试纸条的研制

建立了一种快速、简单的检测牛乳中新霉素残留量的胶体金免疫层析法。将不同浓度的新霉素人工合成完 全抗原包被在硝酸纤维素膜上作为检测线（T1、T2线）,与待测牛乳样品中的新霉素竞争结合新霉素单克隆抗体- 胶体金标记物,通过两条T1、T2线显色情况使传统新霉素胶体金试纸条由定性检测准确到半定量检测。试纸条对 牛乳样品的半定量检测限分别为200 μg/kg和400 μg/kg,该检测限满足欧盟及国家对新霉素检测的需求,且检测牛 乳样品能够满足现场快速检测的要求,为现场快速检测牛乳中新霉素残留提供了更精确的参考依据。     

氯化钙对花生中黄曲霉毒素B1提取及其快速检测结果的影响

以氯化钙为蛋白沉淀剂、黄曲霉毒素B1为靶标,探究了70％甲醇水（V/V）提取液中不同含量氯化钙对花生中黄曲霉毒素提取及其免疫检测结果的影响;采用样品加标回收的方法,研究比较了五种不同含量氯化钙对胶体金免疫层析试纸条和ELISA检测结果的影响。研究结果表明,样品经含1％CaCl2（m／V）的甲醇水处理后,用胶体金免疫层析试纸条检测时,试纸条T线颜色梯度变化,不同浓度加标回收率等参数均得到明显改善,前处理效果显著;选取20份花生实际样品,经过这种前处理之后,进行胶体金免疫层析试纸条和ELISA检测,同时将其检测结果与免疫亲和层析高效液相色谱法（IAC-HPLC）进行比对,胶体金免疫层析试纸条与IAC-HPLC检测结果符合率为90％,间接竞争ELISA与IAC-HPLC检测结果相关系数达0．996,表明本研究所改进的样品前处理方法能提高免疫检测准确度,具有很好的应用性。     

胶体金免疫层析法定量检测猪肉中克伦特罗

建立了基于T/C比值的胶体金免疫层析法快速定量检测猪肉中克伦特罗残留的新方法。胶体金免疫层析试纸条的定量检测线性范围为0.1～1.5 ng/g,检测猪肉中克伦特罗残留的最低检测灵敏度为0.19 ng/g。比较了5种猪肉组织样本中克伦特罗的简便提取方法,其中采用0.02 mol/L,含2.8%NaCl的HCl溶液抽提猪肉样品2次的提取方案,克伦特罗的平均回收率达到76.7%,变异系数为7.4%。实际样本加标回收实验显示,加标量为0.5、1.0、2.0及3.0 ng/g时,胶体金试纸条检测回收率分别为(60.4±12.8)%,(70.24±4.2)%,(75.9±4.9)%,(71.1±5.0)%。与传统ELISA方法比对,结果显示2种方法具有较好的相关性(R2=0.9136)。以上实验结果证实,基于T/C比值法的胶体金免疫层析试纸条可用于猪肉组织样品中克伦特罗的快速及定量检测。     

T-2毒素快速定量检测试纸条的研究

为研制一种快速定量检测玉米中T-2毒素含量的胶体金试纸条,对T-2毒素单克隆抗体进行标记并对胶体金试纸条性能进行研究。用胶体金标记T-2毒素单克隆抗体,通过测定加入不同量碳酸钾后吸光度值的变化,确定标记的最佳p H值,通过与抗原进行正交试验确定最佳组合条件,应用胶体金定量读数仪通过检测线和对照线的对比,检测试纸条的性能。结果表明,单克隆抗体标记的最佳pH值为8.5,最佳标记浓度为20μg/m L,抗原的包被浓度为0.5 mg/mL,羊抗鼠IgG的包被浓度为1.0 mg/mL,试纸条检测T-2毒素标准品的检测限为5μg/kg。T-2毒素胶体金快速定量检测试纸条检测方法可得出具体数据,与常见真菌毒素无交叉反应,回收率在77%～117.6%之间,批内和批间重复性检测变异系数小于10%,玉米中T-2毒素的检测结果与高效液相法检测结果一致。T-2毒素胶体金快速定量检测试纸条可用于玉米中T-2毒素含量的快速定量检测。     

应用胶体金免疫层析试纸条技术 让食品安全检测更高效

正胶体金免疫层析技术(colloidal gold immunochromatography strip,CGIS)为免疫层析试纸条检测技术的延伸,免疫层析试纸条技术具有快速方便、操作简单、特异性强、灵敏度高、能够进行现场快速检测等优点,在食品安全检测方面具有很大的应用潜力以及发展空间。一、原理CGIS主要依靠抗原和抗体能够进行特异性结合的基本原理。胶体金通常是指直径在1nm-150nm之间的细小颗粒,在弱碱性环境下带负电,能与带有正     

胶体金免疫层析法快速检测氯霉素残留

为建立用于快速检测样品中氯霉素残留含量的胶体金免疫层析试纸条，采用免疫竞争法，将抗氯霉素单克隆抗体一胶体金复合物包被在胶体金结合垫上，并将人工合成的氯霉素抗原包被在硝酸纤维素薄膜表面作为检测线（T线），其与待测样品中氯霉素竞争结合胶体金标记的氯霉素单克隆抗体，并能以颜色直观显示检测的定性结果。检测虾肉等组织试样时，灵敏度最低值可达到1ng／ml，只需5—10min，与类似物无交叉反应。试纸条具有较高的灵敏度及特异性，操作便捷．稳定可靠，可作为氯霉素残留现场监控的有效筛检手段。     

苯甲酸免疫胶体金快速检测试纸条的研制

应用胶体金免疫层析技术,制备苯甲酸胶体金免疫层析快速检测试纸条,采用柠檬酸三钠还原法制备颗粒直径为17nm的胶体金,将苯甲酸金标抗体喷涂在玻璃纤维垫上制成胶体金结合垫,将包被抗原和二抗羊抗兔分别结合于硝酸纤维膜作为检测线(T线)和质控线(C线),组装成胶体金免疫层析试纸条并进行灵敏度测试.结果显示,胶体金试纸条检测限为100μg/L,可在5～7min内完成测试,与苯酚、甲苯、苯乙酸、苯丙氨酸等药物均无交叉反应,检测结果与酶联免疫吸附法完全一致.该方法具有操作简便、快速、特异性强、灵敏度高等特点,适用于现场快速检测和筛选工作,具有广泛的商业开发应用前景.     

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.     

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.     

Analysis for organic residues from aids to polymerization used to make plastics intended for food contact

Polymers intended for food contact use have been analysed for organic residues which could be attributed to a range of substances employed as polymerization aids (e.g. initiators and catalysts). A wide range of polymers was extracted with solvents and the extracts analysed by gas chromatography-mass spectrometry (GC-MS). The overwhelming majority of substances identified were not derived from aids to polymerization but were oligomers, additives and adventitious contaminants. However, a small number of substances were identified as initiator residues. These included tetramethylsuccinonitrile (TMSN) which was observed in two polymers and it derived from recombination of two azobisisobutyronitrile (AIBN) initiator radicals. Methyl benzoate, benzoic acid, biphenyl and phenyl benzoate were detected in one poly(methyl methacrylate) sample and in two polyvinylchlorides and they are thought to be derived from benzoyl peroxide initiator. TMSN was subsequently targeted for analysis of poly-(methyl methacrylate) plastics using proton nuclear magnetic resonance spectrometry (¹     

Tests of potential functional barriers for laminated multilayer food packages. Part II: Medium molecular weight permeants

Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. I: Interlaboratory studies of methods of analysis

This paper describes the first part of a project undertaken to develop mussel reference materials for Paralytic Shellfish Poisoning (PSP) toxins. Two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin (STX) and decarbamoyl-saxitoxin (dc-STX) in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the second part of the project: the certification exercise. In the first study, 18 laboratories were asked to measure STX and dc-STX in rehydrated lyophilized mussel material and to identify as many other PSP toxins as possible with a method of their choice. In the second interlaboratory study, 15 laboratories were additionally asked to determine quantitatively STX and dc-STX in rehydrated lyophilized mussel and in a saxitoxin-enriched mussel material. The first study revealed that three out of four postcolumn derivatization methods and one pre-column derivatization method sufficed in principle to determine STX and dc-STX. Most participants (13 of 18) obtained acceptable calibration curves and recoveries. Saxitoxin was hardly detected in the rehydrated lyophilized mussels and results obtained for dc-STX yielded a CV of 58% at a mass fraction of 1.86 mg/kg. Most participants (14 out of 18) identified gonyautoxin-5 (GTX-5) in a hydrolysed extract provided. The first study led to provisional criteria for linearity, recovery and separation. The second study revealed that 6 out of 15 laboratories were able to meet these criteria. Results obtained for dc-STX yielded a CV of 19% at a mass fraction of 3.49mg/kg. Results obtained for STX in the saxitoxin-enriched material yielded a CV of 19% at a mass fraction of 0.34mg/kg. Saxitoxin could not be detected in the PSP-positive material. Hydrolysis was useful to confirm the identity of GTX5 and provided indicative information about C1 and C2 toxins in the PSP-positive material. The methods used in the second interlaboratory study showed sufficiently consistent analysis results to undertake a certification exercise to assign certified values for STX and dc-STX in lyophilized mussel.     

The Ministry of Environmental Protection Issued "Feasible Technology Guidelines for Pollution Prevention and Control in Wood Pulping Process of the Paper Industry (Trial)" and Two Other Guiding Technical Documents

On December 27t＂, 2013, the Ministry of Environmenta Protection announced that, in order to implement ＂The Environmental Protection Law of the People＇ s Republic of China＂, improve the working system in environmenta protection technologies, and promote technologica advancement in pollution prevention, the Ministry of Environmental Protection sponsored the formulation of three guiding technical documents including ＂Feasible Technology Guidelines for Pollution Prevention and Contro n Wood Pulping Process of the Paper Industry （Trial）＂     

1~(st) Intelli-Tissue~ EcoEc Tissue Machine Supplied by PMP Group Successfully Put into Operation in China

正On April 29th,2014,Intelli-Tissue EcoEc tissue machine supplied by PMP Group successfully put into operation at Hebei Xuesong Paper Co.,Ltd.,this is the first such kind of paper machine of PMP Group in China.