液相色谱-串联质谱法测定皮革中PFOS及PFOA盐类

建立了皮革中全氟辛烷磺酸盐(PFOS)及全氟辛酸盐(PFOA)的萃取及液相色谱-串联质谱(LC-MS/MS)的检测方法.采用索氏抽提进行萃取,溶剂为甲醇,萃取液经弱阴离子固相萃取柱(Oasis WAX)净化处理后,采用负离子电喷雾电离、多级反应离子监测(MRM)模式进行LC-MS/MS检测.结果表明,PFOS和PFOA浓度在1 ～50 μg/L范围内,线性相关系良好,相关系数均大于0.995,在10 ～160 mg/kg范围内的添加水平回收率为80%～105%,相对标准偏差为6.3%～15.5%(n=6),定量检出限均为0.5 mg/kg.该方法可用于皮革中PFOS及PFOA盐类物质的测定.     

SPE-HPLC/MS法监测蓝莓等浆果中氟啶虫酰胺和溴氰虫酰胺残留

建立一种采用固相萃取净化提取蓝莓等浆果中的氟啶虫酰胺和溴氰虫酰胺,液相色谱-质谱法定性定量检测的分析方法。蓝莓等浆果均质后,采用乙腈提取,固相萃取净化、富集,收集液经氮吹近干,甲醇定容,液相色谱-质谱仪定性定量检测。结果表明:氟啶虫酰胺和溴氰虫酰胺在0.02～1.0μg/m L质量浓度范围内线性关系良好,相关系数(R2)均大于0.995;氟啶虫酰胺和溴氰虫酰胺检出限分别为0.001 3 mg/kg和0.002 1 mg/kg;加标回收率(0.02, 0.1和0.5μg·m L-1)分别在87.7%～90.7%和88.6%～103.4%之间;重复性与精密度相对标准偏差均在5.0%以内(n=6)。该方法具有灵敏度高、前处理简单、重复性好等优点,适用于蓝莓等浆果中氟啶虫酰胺和溴氰虫酰胺的检测。     

固相萃取-GC-ECD法测定草莓中的4种菊酯类农药

目的:建立利用固相萃取富集草莓中的农残,GC-ECD检测的方法。方法:草莓样品处理后,用乙腈进行提取,提取液经氨基固相萃取柱净化,ECD检测器检测,基质标进行定量分析。结果:4种菊酯类农药质量浓度在0.02~3.0μg/m L范围内,线性良好;联苯菊酯、氯氟氰菊酯、氟胺氰菊酯、氰戊菊酯检测限分别为0.0005mg/kg,0.0003mg/kg,0.001mg/kg,0.001mg/kg;样品加标回收率在85.3%~99.1%;重复性试验RSD小于5%(n=6)。结论:实验证明该方法前处理简单,灵敏度高,重复性好,适用于草莓中农残的检测。     

饲料中11种拟除虫菊酯农药残留的检测方法

建立了一步提取三步净化法-气质联用技术检测饲料中四氟甲醚菊酯、胺菊酯、联苯菊酯、甲氰菊酯、三氟氯氰菊酯、氯菊酯、氯氰菊酯、氟氰戊菊酯、氰戊菊酯、氟胺氰菊酯、溴氰菊酯等11种拟除虫菊酯农药残留的方法。样品经乙腈-水(体积比2∶1)溶液提取,正己烷萃取,再经正己烷饱和的乙腈萃取,固相萃取三步净化过程,经DB-5MS色谱柱分离,以氦气为载气,以选择离子扫描方式(SIM)检测。结果表明,方法线性相关系数r≥0.9893,仪器定量限为0.10~5.00μg/kg。样品加标的平均回收率为82.82%~118.54%,相对标准偏差为3.11%~9.22%。     

吸附剂提取-GC/MS法测定农田水中的8种常用农药

建立气相色谱-质谱(GC-MS)法同时检测农田水中8种常用农药(毒死蜱、乙酰甲胺磷、丙溴磷、高效氯氟氰菊酯、溴氰菊酯、氯氰菊酯、噻虫嗪、氟虫氰)的方法。农田水样品经吸附剂提取、净化等预处理,用乙腈-冰乙酸(9︰1, V/V)作为提取液,无水硫酸镁和十八烷基硅烷(C18)粉末净化,净化液用丙酮定容至1.0 mL, 0.22μm滤膜过滤,经气相色谱仪-质谱联用仪定性定量检测。结果表明, 8种常用农药在0.05～25μg/m L范围内线性关系良好, R2均小于0.995;检出限在0.008～0.020 mg/kg之间,加标回收率(低点0.05 mg/kg、中点1.0 mg/kg、高点10.0 mg/kg)均在83.6%～105.5%之间;重复性RSD为3.42%～4.92%(n=6),精密度RSD为1.69%～2.64%(n=6)。该方法具有前处理提取快速、检出限低、检测结果准确等优点,可用于农田水中常用农药的监测。     

固相萃取-气相色谱法测定坚果中3种拟除虫菊酯残留量

采用固相萃取-气相色谱法测定坚果中氯氰菊酯、氰戊菊酯、溴氰菊酯残留量等3种拟除虫菊酯。坚果样品采用石油醚提取,固相萃取小柱净化,丙酮-石油醚(1+9)洗脱,用Agilent DB-17色谱柱分离,电子捕获检测器检测。试验结果表明,3种拟除虫菊酯农药的色谱图分离效果良好,在0.05μg/mL～0.8μg/mL范围内,检出限为0.001 5 mg/kg～0.002 4 mg/kg,回收率在94.2%～107.0%之间,相对标准偏差(n=6)为0.93%～3.88%。     

皮革中2-巯基苯并噻唑含量的HPLC测试

建立了皮革中2-巯基苯并噻唑(MBT)含量的液相色谱(HPLC)测试方法。采用超声波辅助乙腈对样品进行萃取,重复萃取1次,萃取时间60min,萃取液经膜过滤后,采用带预净化柱的HPLC进行测试,检测波长λ=320nm,流动相为v(乙腈)/v(水)=70/30,等梯度洗脱。方法的检测限为10mg/kg,回收率在93%~103%之间,精密度在3%~9%之间。对20块皮革样品中MBT含量进行测试,样品检出率为30%,含量在37~137mg/kg之间。     

SPE-UPLC-MS/MS法测定烟草及烟草制品中抑芽丹残留量

为准确测定烟草及烟草制品中抑芽丹的残留量,建立了一种固相萃取-超高效液相色谱-串联质谱(SPE-UPLC-MS/MS)方法。烟草样品经盐酸溶液加热回流提取、石墨化炭黑(GCB)SPE柱净化后在多反应监测负离子模式下测定,采用氘代抑芽丹同位素内标法定量。结果表明:(1)使用石墨化炭黑SPE柱可有效净化萃取液,除去盐酸后的洗脱液pH近中性,适合于质谱分析;(2)抑芽丹定量限为0.47 mg/kg,回收率为94.2%~102.1%,相对标准偏差(RSD)小于6%;(3)采用该方法检测了13个烟草样品中的抑芽丹残留量,并与采用YC/T 405.5—2011标准方法的测定值进行比较,结果显示两组数据的一致性较好。该方法灵敏度高,稳定性和准确性好,适用于烟草样品中抑芽丹残留量的测定。     

高效液相色谱法检测果蔬饮料中齐墩果酸和熊果酸

建立一种快速、有效的固相萃取-高效液相色谱法测定果蔬饮料中齐墩果酸、熊果酸的方法。样品经乙醇提取后,采用氨基固相萃取小柱进行净化和富集。采用Waters RP C18色谱(4.6mm×250mm,5μm)分离,以甲醇︰0.1%磷酸溶液(85︰15)作为流动相,用PDA检测器检测,外标法峰面积定量。结果表明,齐墩果酸、熊果酸标准在10.0μg/m L~100.0μg/m L浓度范围内线性良好,相关系数均r~2均为0.999,齐墩果酸组分的LOD为0.05 mg/kg,LOQ为0.15 mg/kg,熊果酸组分的LOD为0.08 mg/kg,LOQ为0.24 mg/kg,加标回收率达到87.9%~94.1%。该方法具有前处理简单、净化效果好、灵敏度高和检测速度快的优点,适用于果蔬饮料中齐墩果酸、熊果酸的富集和定量检测。     

烟草中溴菌腈农药残留检测方法及消解动态

为摸清溴菌腈在烟草中的农药残留消解动态规律及残留特征,建立了QuEchERS前处理和气相色谱-串联质谱(GCMS/MS)检测相结合的烟叶中溴菌腈残留量的分析方法。烟叶经乙腈提取,N-丙基乙二胺吸附剂(PSA)净化,气相色谱-串联质谱法检测。结果表明,在0.01~1.0 mg/kg 3个添加水平下,溴菌腈在鲜烟叶和干烟叶中的平均回收率分别为85.8%~94.5%、83.2%~110.0%,相对标准偏差(RSD)分别为1.4%~10.6%、7.3%~14.1%,定量限(LOQ)均为0.01 mg/kg。利用山东和湖南2年2地的溴菌腈在烟叶中农药残留田间试验样品进行了深入研究,溴菌腈在烟叶中的半衰期7.8~14.9 d;按照162 g.a.i./hm²和243 g.a.i./hm²剂量,分别灌根施药1~2次,末次施药14 d后,溴菌腈在烟叶样品中的最终残留量为0.010~0.13 mg/kg。根据烟草青枯病发病条件、发病时期、农药在烟叶中使用情况及OECD农药残留限量计算结果,建议溴菌腈在烟叶中残留限量为0.2 mg/kg,安全间隔期为14 d。     

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.