UPC~2-MS/MS测定烟用纸张中偶氮染料释放的芳香胺

为测定烟用纸张中偶氮染料释放的芳香胺,通过优化实验条件,建立了一种测定偶氮染料释放的芳香胺的超高效合相色谱-串联质谱(UPC~2-MS/MS)法。样品经连二亚硫酸钠还原、固相萃取净化、C_(18)色谱柱分离后,在多反应监测模式(MRM)下进行MS/MS分析,采用内标法定量。结果表明:(1)各化合物在20～500 ng/mL范围内线性关系良好(R~20.99),检出限(LOD)和定量限(LOQ)分别为0.16～0.42和0.51～1.52 mg/kg,除2,4-二氨基甲苯和2,4-二氨基苯甲醚外,其余19种芳香胺的回收率为73.5%～95.0%,相对标准偏差(RSD)7.0%。(2)采用该方法对30个实际样品进行检测,仅有2个样品在经连二亚硫酸钠还原后检出了部分芳香胺,检测结果与标准方法(GC-MS)结果吻合。该方法分析速度快,分辨率高,溶剂消耗少,适用于烟用纸张中偶氮染料释放的芳香胺的检测。     

纸质食品包装材料中禁用芳香胺迁移量的测定

用去离子水浸泡纸质食品包装材料,提取其中的禁用芳香胺,浸泡液过固相萃取小柱后,用甲醇淋洗,淋洗液经浓缩后用甲醇定容,进行气相色谱/串联质谱法测定.采用的测定模式为三重四级杆质谱电子轰击多反应监测模式,从而建立了一个同时测定纸质食品包装材料中禁用芳香胺迁移量的气相色谱/串联质谱方法,该方法的加标回收率为63.1％ ～98.4％,精密度(RSD)为2 6％～16.2％,在S/N(信噪比)=10的条件下,所有24种禁用芳香胺的检出限均小于1.0 ng/mL.     

LC-MS/MS同时测定卷烟主流烟气中4种芳香胺

建立了测定卷烟主流烟气中4种主要芳香胺(1-氨基萘、2-氨基萘、3-氨基联苯和4-氨基联苯)的液相色谱-串联质谱(LC-MS/MS)方法,对国内外不同焦油含量卷烟烟气中4种芳香胺的含量进行了检测,并与GC/MS方法进行了比较。结果表明:①4种芳香胺的检测限在0.016～0.038 ng/mL之间,方法回收率在70.5%～116.5%之间,日内精密度小于6%,日间精密度小于9%;②与GC/MS测定结果相比较,二者的相关性较好。该方法快速、灵敏、操作简单,适合于卷烟主流烟气中4种芳香胺的同时测定。     

气相色谱/串联质谱法测定纺织品中的禁用芳香胺

纺织品中的偶氮染料经柠檬酸缓冲液提取后,再用连二亚硫酸钠将其还原裂解成为胺类物质,经液-液萃取、浓缩处理后,所得残渣用甲醇溶解,通过HP-5MS色谱柱分离,采用串联质谱进行测定,测定模式为三重四级杆质谱电子轰击多反应监测模式,从而建立了一个同时测定纺织品中24种禁用芳香胺的气相色谱/串联质谱方法。该方法的加标回收率为63.4%~98.2%,RSD为2.8%~15.7%,在S/N=10的条件下,所有禁用芳香胺检出限均小于1.0ng/mL。该方法简便快速,可用于纺织品中禁用芳香胺的检测。     

液相色谱串联质谱法测定纸制食品接触材料中芳香族伯胺迁移量

目的 建立纸制食品接触材料中24种芳香族伯胺迁移量的液相色谱串联质谱检测方法。方法 以不同种类食品模拟物进行模拟迁移实验, 模拟迁移液过0.22 μm滤膜测定。液相色谱使用ZORBAX-C18反相色谱柱, 以乙腈和0.1%甲酸为流动相, 在梯度条件下分析。在正离子模式下多反应监测(MRM) 采集质谱信号, 进行定性和定量分析。结果 24种初级芳香胺在50%乙醇溶液(v/v)模拟物中标准曲线的线性相关系数为0.9876~0.9999, 加标回收率为72.98%~97.88%, 相对标准偏差均在0.30%~9.90%, 定量限均小于或等于3.0 μg/kg。结论 该方法快速简便、灵敏度高、准确性好, 满足了相关法规的限量测定要求。     

液相色谱-串联质谱法测定粮谷中的噁唑酰草胺

为建立粮谷中噁唑酰草胺的液相色谱串联质谱法,采用液相色谱-串联质谱法,使用C_(18)反相色谱柱,用外标法对噁唑酰草胺进行定性定量分析。对空白粮谷样品进行的3个水平(20.0, 80.0和200μg/kg)的添加回收试验,结果表明,该方法的回收率在80.6%～96.6%之间,相对标准偏差为0.45%～3.84%(n=3),线性相关系数为0.999 9,方法检出限为2.00μg/kg。该方法快速、简便,适用于粮谷中噁唑酰草胺的测定。     

HPLC-MS/MS法测定烟用纸张中的高氯酸根

为快速、准确测定烟用包装材料中的高氯酸根,建立了测定烟用纸张(接装纸、内衬纸、条与盒包装纸)中高氯酸根离子的高效液相色谱-串联质谱(HPLC-MS/MS)方法。样品经水提取、多级固相萃取柱净化后,采用阴离子分析柱,以乙腈-乙酸铵水溶液为流动相进行色谱分离,在多反应监测(MRM)模式下进行质谱测定。结果表明:1~(18)O标记高氯酸根离子内标的加入及样品的多级净化有效降低了基质效应;2在0.2~20.0μg/L质量浓度范围内,标准曲线线性关系良好(R20.995);加标回收率为95.2%~105.5%;日内和日间相对标准偏差均8%;检出限和定量限分别为1.13和3.77μg/kg。3在所测定的100个样品中,高氯酸根离子的检出率为9%,最高检出量为0.048 mg/kg,远小于美国食品药品监督管理局(US FDA)所规定的食品包装材料中允许的最高限量。该方法操作简便、灵敏度高、准确性好,适用于烟用纸张中高氯酸根离子的测定。     

液相色谱-串联质谱法测定腐乳中的生物胺

建立了一种使用液相色谱-串联质谱（LC-MS/MS）技术检测腐乳中9种生物胺的方法。样品经5%三氯乙酸水溶液提取后,进行液相色谱-串联质谱法测定,采用外标法定量。对检测方法进行方法学验证,9种生物胺在质量浓度为10～200 ng/mL范围内线性相关系数R2＞0.999,方法检出限为0.03 mg/kg,定量限为0.1 mg/kg,回收率在85%～101%之间,相对标准偏差（RSD）在0.9%～4.8%之间。该方法结果精密、准确、重复性好、操作简单,适用于腐乳中9种生物胺的测定。     

LC-MS/MS法测定烟用纸张中的五氯苯酚

建立了测定烟用纸张中五氯苯酚的液相色谱-串联质谱法(LC-MS/MS)。烟用纸张样品超声提取后直接进样,在Atiantis d C18柱上以甲醇-水(含0.1%甲酸)为流动相进行分离,用LC-MS/MS在多反应监测(MRM)模式下测定,内标法定量。结果表明:1方法的线性范围是1~20 ng/mL,线性关系良好(R20.99),平均回收率91.6%,相对标准偏差(RSD)8%(n=5),定量限为0.018 mg/kg。2样品前处理过程简单,无需复杂的衍生化操作。建立的方法适用于烟用纸张中五氯苯酚的快速检测。     

QuEChERS-超高效液相色谱-串联质谱法测定柑橘中呋虫胺和螺虫乙酯残留量

目的建立QuEChERS-超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)同时测定柑橘中咲虫胺及螺虫乙酿残留量的分析方法。方法样品采用QuEChERS方法,经1%甲酸乙腈涡旋振荡提取,无水硫酸镁和氯化钠盐析后,经乙二胺-N-丙基硅烷、C_(18)混合净化剂净化,用Waters ACQUITY UPLC HSS T_3色谱柱分离,超高效液相色谱-串联质谱正离子扫描、多反应监测模式进行测定,外标法定量。结果呋虫胺及其代谢物、螺虫乙酯及其代谢物在相关浓度范围内线性关系良好,相关系数均大于0.99。呋虫胺及其代谢物的回收率为86.8%～97.6%,相对标准偏差为2.7%～6.8%,方法定量限为0.005～0.01 mg/kg;螺虫乙酯及其代谢物的回收率为85.8%～96.9%,相对标准偏差为3.2%～7.4%,方法定量限为0.005～0.008 mg/kg。结论该方法样品前处理过程简单快速,分析时间短,定量限低、正确度及精密度均符合农药残留检测要求,适用于同时测定柑橘中呋虫胺和螺虫乙酯残留。     

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.