浊点萃取-高效液相色谱法测定牛奶中的 双酚A和壬基酚

目的 建立浊点萃取-高效液相色谱相结合检测牛奶中双酚A和4-n-壬基酚的分析方法。方法 应用浊点萃取(CPE)对牛奶中的双酚A和4-n-壬基酚进行萃取富集。研究确立了牛奶体积为10mL时,冰乙酸体积为200 μL,无水硫酸钠质量为0.900 g,离心参数为9917.355 g（10000 r/min）、8℃、10 min的最佳破乳条件; 最佳浊点萃取条件为: Tween 20的浓度为100g/L,无水硫酸钠的质量为0.020g,正丁醇的体积为200μL,平衡温度为60℃,平衡时间为30min。结果 双酚A在0.05-2.00mg/L,壬基酚在0.1~5.00mg/L范围内呈良好的线性关系,线性相关系数均大于0.999,双酚A的加标回收率在85.60～91.20 %之间,壬基酚在71.30~73.30%之间,RSD为3.42～9.85 %,方法的检出限分别为7.36 μg/kg、93.19μg/kg。结论 该方法具有有机试剂用量少、灵敏度高、绿色环保以及操作简单等特点, 对于牛奶中的双酚A和壬基酚有着良好的检测效果。     

高效液相色谱法检测运动饮料中双酚A的残留

建立一种快速、有效的高效液相色谱法测定运动饮料中双酚A残留的方法。样品经乙醇提取后,采用C18固相萃取小柱进行净化和富集。采用苯基色谱柱(4.6 mm×250 mm,5μm)分离,以乙腈∶水=40∶60(体积比)作为流动相,用PDA检测器检测,外标法峰面积定量。结果表明,双酚A标液在0.10μg/m L~1.00μg/m L浓度范围内线性良好,相关系数r~2为0.999,检出限为5.0μg/kg,定量限为15.0μg/kg,加标回收率达到92.1%~93.8%。该方法具有前处理简单、富集效果好和检测速度快的优点,适用于运动饮料中双酚A残留的定量检测。     

婴幼儿配方乳粉中7种酚类环境激素的测定

目的 建立婴幼儿配方乳粉中双酚A(BPA)、双酚F(BPF)、己烷雌酚、己烯雌酚、双烯雌酚、辛基酚、壬基酚7种酚类环境激素的液相色谱-串联四极杆质谱检测方法。方法 以1%三氯乙酸和乙腈提取, HLB固相萃取净化, 由C18液相色谱柱分离, 以电喷雾离子源负离子模式, 多反应监测(MRM)条件下对7种物质进行检测, 基质加标标准曲线法定量。结果 7种化合物检出限在0.5~5 μg/kg, 定量限从1.5~15 μg/kg。7种物质从定量限到50 ng/mL范围内线性关系良好。在三水平加标回收试验中, 7种化合物的回收率在73.5%~97.9%之间, RSD为5.6%~13.6%。结论 本文对 7种环境激素同时检测的方法具有准确、高效、灵敏、特异性强等优点, 为食品安全风险监控方法提供参考依据。     

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%.     

固相萃取-超高效液相色谱-三重四极杆质谱法同时测定饲料中5种雌激素

建立了固相萃取-超高效液相色谱-三重四极杆质谱法(SPE-UPLC-MS/MS)同时测定饲料中双烯雌酚、己烯雌酚、己烷雌酚、17α-雌二醇和17β-雌二醇5种激素的检测方法。饲料样品采用乙醚振荡提取、三氯乙酸除蛋白和正己烷除脂,提取液通过Max固相萃取柱净化,经过Athena C18-WP色谱柱(2.1×150 mm,5μm)分离,以0.25‰氨水和乙腈进行梯度洗脱,负离子电喷雾电离多反应监测模式进行定性和定量分析。同时优化液相色谱条件和质谱参数,以提高灵敏度,并以17β-雌二醇-D3和己烯雌酚-D8为内标进行定量。结果显示,5种激素在0～10μg/L范围内线性相关系(r)≥0.9994;5种雌激素的定量限均为1.0μg/kg;各雌激素的加标浓度为1.0μg/kg、2.0μg/kg、5.0μg/kg时,其加标回收率均在70.20%～114.37%之间,相对标准偏差为0.15%～9.08%(n=6)。结果表明,该方法前处理简单、准确可靠,适用于饲料中5种雌激素的检测。     

高效液相色谱-串联质谱法测定纺织品中四溴双酚A

建立了纺织品中四溴双酚A的高效液相色谱-串联质谱(HPLC-MS/MS)测定方法。样品经甲醇超声萃取后,萃取液在多重反应监测模式下检测。结果表明：四溴双酚A在10～100μg/L质量浓度范围内呈良好的线性关系,相关系数(r~2)可达0.999 8,方法检出限为21.5μg/kg;在3个加标浓度水平下的平均回收率为88.8%～119.0%,相对标准偏差(RSD,n=6)为2.5%～5.0%。该方法操作简单,精密度好,适合多种纺织品材料中四溴双酚A的分析检测。     

QuEChERS-SPE快速样品制备-超高效液相色谱-串联质谱联用法测定婴幼儿配方奶中双酚类化合物

建立QuEChERS-固相萃取（quick, easy, cheap, effective, rugged, safe-solid phase extraction,QuEChERS-SPE）样品净化,超高效液相色谱-串联质谱测定婴幼儿配方奶中8 种双酚类化合物残留的方法。样品中的双酚类化合物残留经乙腈提取,QuEChERS-SPE净化样品,基质匹配标准校正外标法定量。结果表明,样品经净化和校正后8 种双酚类化合物的基质因子为0.80～1.20;在线性范围内,8 种双酚类化合物线性相关系数（R2）均大于0.999。方法回收率为50.2%～116%（n=6）,相对标准偏差为0.5%～14%（n=6）,方法的检出限和定量限：固体奶粉为0.017～0.78μg/kg及0.055～2.6μg/kg,液体奶为0.0011～0.055μg/L及0.0035～0.18μg/L。采用本方法对中国和加拿大市场购买的婴幼儿配方奶进行检测,根据测定的含量和婴幼儿每天摄入奶量,可分别计算出婴幼儿可能最多摄入双酚A、双酚S、双酚F的量分别为0.065、0.050、0.0059μg/（kg·d）,但均未超过欧洲食品安全协会对双酚类化合物从食品包装材料迁移到食品中限量的规定（4μg/（kg·d））。     

超高效液相色谱-串联质谱法快速测定婴幼儿配方奶粉中双酚A和壬基酚

建立快速测定双酚A和壬基酚的超高效液相色谱-串联质谱法能加强婴幼儿配方奶粉中污染项目的风险监测。婴幼儿配方奶粉样品经乙腈两次提取，通过冷冻、离心、氮吹等过程进行除杂和浓缩，采用C18色谱柱分离，以0.05%氨水（v/v）和甲醇为流动相进行梯度洗脱，SRM模式检测双酚A和壬基酚，内标法定量，标准曲线比较法评估基质效应。结果表明，双酚A和壬基酚的方法检出限为1μg/kg，定量限为2μg/kg；线性范围为0.5～50 ng/mL；通过线性范围内3个水平的加标，双酚A、壬基酚回收率分别为85.04%～109.08%、84.52%～113.32%；双酚A、壬基酚的仪器精密度分别为5.65%、3.86%，方法精密度分别为5.04%、3.10%；基质效应考察表明，壬基酚无基质效应，双酚A则存在明显基质抑制（ME=60.2%），故需采用内标校正。本方法限值低、分析时间短、前处理简单，适用于婴幼儿配方奶粉中双酚A和壬基酚的同时测定。     

液相色谱-质谱联用技术检测婴幼儿乳粉中的丙烯酰胺

建立了婴幼儿乳粉中的丙烯酰胺的高效液相色谱-串联四极杆质谱联用测定方法。样品加水溶解超声提取后,利用乙腈除蛋白,正己烷除脂,使用Hypersil GOLD C18柱(50 mm×4.6 mm(i.d.),1.9μm)分离,经梯度洗脱分离,用电喷雾正离子MRM模式检测,同位素内标定量,可以对婴幼儿配方乳粉中的丙烯酰胺进行定量分析。结果表明:该方法的检出限为5μg/kg,定量限为10μg/kg,线性范围10.0μg/L～200.0μg/L,加标回收率介于86.7%～106.8%之间,相对标准偏差3.07%～9.61%(n=6)。     

UPLC-MS/MS同时检测婴幼儿配方乳粉中氯酸盐和高氯酸盐残留

该实验建立了超高效液相色谱-串联质谱法（UPLC-MS/MS）同时测定婴幼儿配方乳粉中氯酸盐和高氯酸盐残留量的方法。样品经甲酸水提取,乙腈沉淀蛋白,乙腈饱和正己烷除去脂肪,采用Anionic Polar Pesticide色谱柱（2.1 mm×150 mm,5 μm）分离,以0.9%甲酸+50 mmol/L甲酸铵水溶液和乙腈为流动相梯度洗脱,在电喷雾离子源负离子（ESI-）多反应监测模式条件下,对氯酸盐和高氯酸盐进行定性和定量分析。结果表明,高氯酸盐和氯酸盐分别在0.5～50.0 μg/L和1.0～100.0 μg/L范围内线性关系良好,高氯酸盐和氯酸盐的定量限（LOQ）分别为7.5 μg/kg和15.0 μg/kg。高氯酸盐和氯酸盐的加标回收率为82.5%～98.5%,精密度试验结果的相对标准偏差（RSD）为2.0%～8.7%;该方法稳定、准确、灵敏度高,可用于婴幼儿配方乳粉中氯酸盐和高氯酸盐残留量检测。     

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.