QuEChERS-气相色谱-三重四极杆质谱法同时测定枸杞中46种农药残留

建立了QuEChERS结合气相色谱-三重四极杆质谱法(GC-MS/MS)同时检测枸杞中46种农药残留的方法。样品经乙腈提取后,使用无水硫酸镁、N-丙基乙二胺(N-propyl ethylenediamine,PSA)进行净化,以HP-5MS色谱柱分离待测物,GC-MS/MS采用多反应监测(multiple reaction monitoring mode,MRM)模式检测,基质匹配外标法定量。结果表明,46种农药在0.01~0.20 μg/mL范围内线性关系良好,相关系数r>0.99。方法检出限(S/N=3)在0.02~3.90 μg/kg的范围内,方法定量限(S/N=10)在0.05~12.99 μg/kg的范围内;在10、50、100 μg/kg的加标水平下,46种化合物平均加标回收率达71.5%~99.8%,相对标准偏差为0.7%~8.9%。10批次枸杞样品中4批次检出农药残留,含量范围为19.4~262 μg/kg。该方法快速、灵敏、准确,适用于枸杞中多种农药残留的检测。     

UPLC-MS-MS快速测定烟草中131种农药残留量

采用QuEChERS-超高效液相色谱-串联质谱法建立了烟草中131种农药残留的同时测定方法,样品用1%乙酸-乙腈萃取,氯化钠和无水硫酸镁盐析,经PSA固相分散吸附剂净化,采用正负离子多反应监测（MRM）模式检测,外标法定量。结果表明,131种农药在1~200 μg/L范围内线性关系良好,决定系数（r²）均大于0.99,方法的检出限为0.05~24.50 μg/kg,131种目标物的平均回收率为65.3%~112.4%,RSD为3.2%~7.3%。该方法简便、快速、灵敏、可靠,适用于烟草中131种农药残留的快速测定。     

QuEChERS/超高效液相色谱-串联质谱法测定茶叶中28种农药残留

建立了QuEChERS/超高效液相色谱-串联质谱（UPLC-MS/MS）测定绿茶中28种农药残留的分析方法。样品经1%乙酸乙腈提取,QuEChERS方法净化后进行UPLC-MS/MS测定。采用电喷雾离子源（ESI）,正离子模式扫描,多反应检测（MRM）模式采集,基质匹配工作曲线法定量。结果表明:28种目标化合物在各自浓度范围内线性良好,相关系数（r）为0.990~0.998,检出限（LOD,S/N≥3）为0.08~1.26 μg/kg,定量限（LOQ,S/N≥10）为0.28~4.20 μg/kg;在10、50、80 μg/kg 3个加标水平下平均回收率为72.5%~118.5%,相对标准偏差（n=6）为0.8%~16.3%。该方法简单、快速、重现性好、稳定性高,可满足茶叶中28种农药残留的检测要求。     

QuEChERS-气相色谱质谱法测定苹果中45种农药残留

建立了QuEChERS-气相色谱质谱法同时测定苹果中45种农药残留检测方法,样品以1%乙酸乙腈提取,经25 mg PSA、25 mg C₁₈和7.5 mg GCB净化,GC-MS选择离子监测(SIM)模式下检测,基质匹配外标法定量。检测结果表明,45种农药在10~200 μg/L质量浓度范围内线性关系良好,各农药的线性相关系数均大于0.995;在30、50和100 μg/kg添加水平下,45种农药的回收率在69.3%~116%之间,相对标准偏差在0.7%~7.9%之间;方法的检出限在1.5~15.0 μg/kg之间,定量限在5.0~50.0 μg/kg之间。该方法准确度高、精密度好、步骤简单、操作快捷、成本低廉,适用于苹果中农药残留的检测。     

液相色谱-串联质谱法测定水果中8种极性农药残留量

目的 建立高效液相色谱-串联质谱法(high performance liquid chromatography-tandem mass spectrometry, HPLC-MS/MS)同时测定水果中8种极性农药残留量的分析方法。方法 样品采用含1%(V:V)乙酸的乙腈溶液提取后, 以PC-HILLIC色谱柱分离待测物, 采用鞘流电喷雾离子化, 正离子扫描和多反应监测模式(multiple reaction monitoring, MRM)检测, 基质匹配标准溶液外标法定量。结果 野燕枯、灭蝇胺和助壮素在0.1~200 μg/L之间, 矮壮素在0.1~500 μg/L, 丁酰肼在1~500 μg/L, 沙蚕毒素在2~1000 μg/L, 敌草快和百草枯在5~1000 μg/L范围内线性关系良好, 相关系数均大于0.990。8种极性农药的方法定量限在0.1~20.0 μg/kg 之间, 样品添加回收试验的平均回收率为73.6%~118.5%, 相对标准偏差(relative standard deviation, RSD)(n=6)在3.4%~17.4%之间。结论 该方法快速简便, 定量准确, 可满足多种水果中8种极性农药的残留检测要求。     

QuEChERS-HPLC-MS/MS测定蔬菜中29种农药残留

建立了QuEChERS-高效液相色谱-串联质谱（HPLC-MS/MS）同时快速测定蔬菜中29种农药残留的分析方法。样品以乙腈提取,氯化钠盐析,以十八烷基硅烷键合硅胶（C18）和N-丙基乙二胺（PSA）净化,以Waters XBridge C18色谱柱分离,电喷雾正离子扫描,多反应监测（MRM）模式检测,基质匹配标准溶液外标法定量。在此优化条件下,29种农药分子在不同加标水平下的平均回收率为64.62%～123.55%,相对标准偏差（RSD）为0.7%～14.3%,方法定量限（LOQ）为0.40～8.00 μg/kg。该方法简便快速、灵敏度高、重现性好,能满足蔬菜中农药残留的快速检测要求。     

QuEChERS-超高效液相色谱-三重四极杆质谱法快速检测主要原粮与油料中101种农药残留

目的 建立QuEChERS-超高效液相色谱-三重四极杆质谱法快速检测主要原粮与油料中101种常见农药残留量的方法。方法 样品加入乙腈后涡旋混匀并超声提取,采用无水硫酸镁和Ｎ-丙基乙二胺固相吸附剂(PSA)净化,以乙腈-0.1%(V:V )甲酸水溶液作为流动相进行梯度洗脱,采用T3色谱柱分离,在多反应监测模式(multiple reaction monitoring, MRM)下进行测定,外标法定量。结果 101种农药残留在3个添加水平（50、100和200 μg/kg ）回收率在62.31%~119.74%之间,相对标准偏差小于15%,定量限为0.0609~23.809 μg/kg。结论 该方法操作简便,快速,有较高的灵敏度和准确度,可应用于主要原粮粮与油料中农药残留日常筛查工作中。     

固相萃取-高效液相色谱-串联质谱法同时测定鸡蛋中42种农药残留

目的 建立固相萃取-高效液相色谱-串联质谱法同时测定鸡蛋中42种农药残留的检测方法。方法 样品经加水分散后,用乙腈提取,PRiME HLB固相萃取柱进行净化处理,采用Shim-pack XR-ODSⅡ色谱柱(75 mm×2.0 mm, 2.2 μm)分离,5 mmol乙酸铵水溶液(A)-甲醇溶液(B)为流动相,进行梯度洗脱;质谱法选择电喷雾离子源ESI,正负离子分段扫描,多反应监测(MRM)模式检测,基质匹配标准溶液外标法定量。结果 42种农药的峰面积与质量浓度在0.1~2 ng/mL范围内呈现良好的线性关系,相关系数r均大于0.994;方法检出限(LOD, S/N=3)为0.04~0.3 μg/kg,定量限(LOQ, S/N=10)为0.1~1.0 μg/kg。在1.0、2.0、5.0、10 μg/kg四个添加水平下,42种农药平均加标回收率为61.0%~118.5%,相对标准偏差为0.8%~9.9%。结论 该方法具有操作简单、分析时间短、试剂用量少、灵敏度高且重复性好等特点,适用于鸡蛋中农药残留的高通量快速检测分析。     

超高效液相色谱-串联质谱法检测桃中13种高关注农药残留

目的 建立一种基于超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)检测桃中13种高关注农药残留的方法。方法 样品采用含1%(体积分数)乙酸的乙腈溶液超声提取, 4 g无水硫酸镁和1 g氯化钠盐析后, 不净化, 直接经Waters HSS T3(2.1 mm×100 mm, 1.8 μm)色谱柱分离, 用甲醇和2 mmol/L甲酸铵水溶液为流动相梯度洗脱, 串联质谱电喷雾正离子扫描, 多反应监测模式检测, 基质匹配标准溶液-外标法定量。结果 13种农药在0.5~8 μg/kg范围内线性关系良好, 相关系数r均大于0.997, 在桃中添加0.5、2和5 μg/kg 3个浓度的农药标准溶液, 平均回收率为63.2%~122.3%, 日内相对标准偏差(RSDs)为0.6%~9.1%(n=6), 日间RSDs为2.8%~ 13.2%(n=3), 定量限均为0.5 μg/kg。结论 该方法适用于桃中13种农药残留的检测。     

PRiME HLB固相萃取-高效液相色谱-串联质谱法同时快速测定鸡蛋中48种兽药残留

建立固相萃取-高效液相色谱-串联质谱同时快速测定鸡蛋中48种兽药残留的分析方法。样品采用90%乙腈水溶液提取,用PRiME HLB小柱净化浓缩后用电喷雾离子源,正负离子扫描,多反应监测模式的高效液相色谱-串联质谱法进行检测,以基质匹配曲线外标法定量。正离子采用CAPCELL PAK C18 MGⅢ-H色谱柱,流动相为0.05%甲酸乙腈和0.1%甲酸水;负离子采用ACQUITY UPLC BEH C18色谱柱,流动相为5 mmol/L乙酸铵和乙腈。结果表明,鸡蛋样品中的48种兽药残留在0.5~50 μg/kg浓度范围内线性关系良好,相关系数(r)为0.9952~1.0000。方法检出限为0.01~0.55 μg/kg,定量限为0.03~1.83 μg/kg,样品回收率在63.3%~111.4%之间,相对标准偏差小于10%(n=3)。本方法操作快速简单,重复性好,灵敏度较高,适用于鸡蛋中48种兽药残留的快速筛查检测。     

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.