高效液相色谱-串联四极杆质谱联用测定饼干中丙烯酰胺残留量

建立饼干中丙烯酰胺残留的高效液相色谱-串联四极杆质谱联用测定方法.该方法经纯水提取样品,以ZORBAX SB-Aq柱(4.6×150mm,5μm)分离,流动相为0.1%甲酸水溶液和乙腈(体积比为97:3),电喷雾正离子MRM模式检测.该方法的检出限0.3μg/L,方法定量下限3.0μg/kg,线性范围0.3μg/L～100.0μg/L,加标回收率91.5%～99.5%,相对标准偏差为4.44%.     

同位素稀释法-超高效液相色谱-串联质谱法测定豆芽中6种喹诺酮类药物残留

目的建立通过式固相萃取(solid phase extraction,SPE)柱净化、氘代同位素内标、超高效液相色谱-串联质谱法同时测定豆芽中6种喹诺酮类药物残留的方法。方法用0.1%甲酸-乙腈作为提取溶剂,经通过式固相萃取柱净化提取液,超高效液相色谱-串联质谱测定豆芽中6种喹诺酮药物残留。结果 6种喹诺酮在5.0～200μg/L范围内线性关系良好,r~2≥0.999;方法检出限(S/N=3)为0.7μg/kg,定量限(S/N=10)为2.0μg/kg;加标水平为2.0～80μg/kg时,平均回收率在85.5%～119.4%,相对标准偏差(relative standard deviation,RSD)(n=6)为0.13%～9 93%。结论本方法前处理简单,定量结果准确,回收率高,可以应用于大批次豆芽中喹诺酮药物残留的监测。     

液相色谱-串联三重四极杆质谱测定饮料中双酚A残留

建立饮料中双酚A残留的高效液相色谱-串联四极杆质谱联用测定方法.方法为:用乙腈处理样品,以ZORBAX XDB-C18柱(2.1 mm×150 mm,5μm)分离,流动相为乙腈和水溶液(梯度洗脱),电喷雾负离子MRM模式检测.该方法的检出限5.0μg/L,方法定量下限10.0μg/L,线性范围5.0μg/L～100.0μg/L,加标回收率96.2%～102.5%,相对标准偏差为2.30%.     

液质联用技术测定茶叶中多菌灵残留

建立茶叶中多菌灵残留的高效液相色谱-串联四极杆质谱联用测定方法。该方法中样品经0.2 mol/L盐酸甲醇溶液(1∶1,υ/υ)超声提取,MCX固相萃取柱净化,以ZORBAX Eclipse XDB-C18色谱柱(3.0 mm×50 mm,1.8μm)分离,流动相为0.1%甲酸水和乙腈(梯度洗脱),电喷雾正离子MRM模式检测。该方法的检出限为1.0μg/kg,线性范围0.5μg/L～3 000μg/L,加标回收率为85.0%～96.0%,相对标准偏差为3.71%。     

通过式固相萃取-超高效液相色谱-串联质谱法测定猪肉和牛肉中9种类固醇激素

建立通过式固相萃取-超高效液相色谱-串联质谱法检测猪肉和牛肉中9种类固醇激素的方法。样品于37℃酶解16 h,乙腈涡旋提取后,经新型PRiME HLB通过式固相萃取小柱净化,采用Waters Acquity BEH C_(18)色谱柱(2.1 mm×100 mm,2.5μm)分离,以体积分数0.1%甲酸水溶液-乙腈为流动相进行梯度洗脱,使用电喷雾离子源正离子模式检测,内标法定量。结果表明:9种类固醇激素在0.2～100.0 ng/mL质量浓度范围内线性关系良好,检出限为0.2～0.5μg/kg,定量限为0.4～1.0μg/kg;方法回收率为84.5%～117.3%,相对标准偏差小于10%。该方法操作简便且灵敏度高,适用于猪肉和牛肉中9种类固醇激素的定量分析。     

固相萃取-超高效液相色谱串联质谱法检测甘蔗中3-硝基丙酸的方法研究

目的建立甘蔗中3-硝基丙酸的固相萃取-超高效液相色谱串联质谱检测方法。方法样品经乙腈萃取,Sep-pak氨基固相萃取柱净化,超高效液相色谱串联质谱法测定甘蔗中3-硝基丙酸含量。色谱柱为WatersACQUITY BEH C18柱(1.7μm,50 mm×2.1 mm),柱温40℃,样品温度10℃,进样体积5μl,流动相A为水,流动相B为乙腈,梯度洗脱。结果方法的线性范围为4.0～40.0μg/kg,基质加标工作曲线线性相关系数为0.998。方法的定性检出限为1.0μg/kg,定量检出限为4.0μg/kg。高、中、低3个浓度水平的加标回收率为92.5%～93.6%,相对标准偏差小于10%。结论本方法灵敏、快速、准确,可用于甘蔗中3-硝基丙酸的测定。     

改进MSPD-HPLC法快速检测猪血豆腐中镇静剂及雌激素残留

建立改进了的基质固相分散萃取(MSPD)-高效液相色谱法(HPLC/UVD)同时快速检测猪血豆腐中的4种镇静剂(艾司唑仑、阿普唑仑、氯氮和地西泮)及己烯雌酚残留的方法。样品以无水硫酸钠和弗洛里西土(质量比4∶1)为分散剂和净化剂,甲醇为溶剂。色谱条件:C18色谱柱(5μm,250 mm×4.6 mm i.d.),甲醇-乙腈-水(体积比30∶30∶40)为流动相,流速:1.0 m L/min,检测波长235 nm,柱温:30℃。5组分在0.010μg/m L~10μg/m L范围内线性关系良好,相关系数均不低于0.999 2。猪血豆腐中4种镇静剂的方法检出限均为10 ng/g,己烯雌酚的方法检出限为15 ng/g;5组分平均回收率在82.4%~104.5%之间,相对标准偏差为1.7%~3.5%。结果表明该方法简便、快速、经济,适用于猪血豆腐中己烯雌酚及多种镇静剂类药物残留的快速检测。     

超高效液相色谱-串联质谱法测定鳗鱼中醋酸甲羟孕酮含量

研究了鳗鱼中醋酸甲羟孕酮的固相萃取-超高效液相色谱-串联质谱分析方法。样品用乙酸乙酯提取,经固相萃取柱净化后,40℃水浴氮气吹至近干;以乙腈和含有0.1%甲酸的水溶液为流动相,经ACQUITYTM UPLC BEH C18柱分离后进行超高效液相色谱-串联质谱多反应监测模式下的定性定量分析。醋酸甲羟孕酮检出限为0.03μg/kg、定量限为0.10μg/kg,添加量为0.10～5.0μg/kg时,醋酸甲羟孕酮在鳗鱼中的平均回收率大于80%,相对标准偏差小于10%。     

QuEChERS-超高效液相色谱-串联质谱法快速检测鸡鸭肉中己烯雌酚残留

建立鸡鸭肉中己烯雌酚(diethylstilbestrol,DES)残留的QuEChERS-超高效液相色谱-串联质谱测定方法。均质样品用水分散后加入乙腈提取,经分散固相萃取净化后,采用XBridge Phenyl-C18色谱柱(150 mm×2.1 mm,3.5μm)分离,在电喷雾电离负离子模式下以多反应监测方式检测,流动相为水-乙腈。结果表明:DES在质量浓度0.50～20.00 ng/mL范围内线性良好,相关系数为0.999 9;3个加标水平的平均回收率为70.4%～81.6%,相对标准偏差为3.1%～3.9%;检出限和定量限分别为0.1、0.4μg/kg。     

液相色谱-串联三重四极杆质谱测定牛奶中的氯霉素残留量

建立牛奶中氯霉素残留的高效液相色谱-串联四极杆质谱联用测定方法。该方法经乙腈提取样品,以MGⅢ-C18柱(2.1×150 mm,1.8μm)分离,流动相为水溶液和乙腈(体积比为65∶35),电喷雾负离子MRM模式检测。该方法的检出限0.07μg/L,线性范围0.05μg/L~20.0μg/L,加标回收率98.5%～110.8%,相对标准偏差为3.57%。     

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.