微波消解-电感耦合等离子体质谱法同时测定蜂胶中的5种重金属元素

目的建立微波消解-电感耦合等离子质谱法(microwave digestion-inductively coupled plasma mass spectrometry,MWD-ICP-MS)同时测定蜂胶中铅(Pb)、砷(As)、汞(Hg)、镉(Cd)、铬(Cr)5种常见重金属元素。方法样品加HNO_3 5.0 m L和H_2O_2 1.0 m L进行微波消解,赶酸温度为110℃;采用ICP-MS法直接测定Pb、As、Hg、Cd、Cr 5种重金属元素的含量。结果 Pb、As、Cd、Cr在1~500μg/L线性范围内,Hg在1~5.0μg/L线性范围内都具有良好的线性关系,相关系数r0.999,检出限为0.012~0.015 mg/kg,加标回收率为95.3%~101.8%。该方法测得蜂胶中的Pb含量为2.16 mg/kg、As含量为0.23 mg/kg、Hg含量为0.03 mg/kg、Cd含量为0.06 mg/kg、Cr含量为1.2 mg/kg。结论该方法具有良好的准确度和精密度,检出限低,适用于蜂胶中常见重金属元素的同时测定。     

微波消解-ICP-MS测定盐酸黄酮哌酯片中重金属含量

目的建立微波消解-电感耦合等离子体质谱(ICP-MS)测定盐酸黄酮哌酯片中5种重金属元素的含量。方法该药物加入浓硝酸进行微波消解后,ICP-MS法测定As、Cd、Pb、Hg、Ni的含量。结果各元素标准曲线的相关系数都大于0.998,检出限0.001～0.028μg/L,平均加样回收率89.7%～106.7%(RSD5.0%)。结论盐酸黄酮哌酯片中As、Cd、Pb、Hg、Ni含量均能满足中国药典、美国药典和人用药品注册技术要求国际协调会议的要求。     

云南野生与栽培茯苓中矿质元素含量研究

建立微波消解-电感耦合等离子体质谱法(ICP-MS)测定云南15个产地野生与栽培茯苓菌核中Fe、Mn、Cu、Zn、Co、Li、V、Ba、Cr、As、Cd、Pb等12种矿质元素,探讨茯苓中矿质元素的含量分布特征。采用SPSS 21.0进行主成分分析和相关性分析。结果显示,线性回归方程相关系数r均大于0.9990,检出限范围在0.009~1.035μg/L之间,参考物菠菜(GBW10015)和灌木枝叶(GBW07603)测定值在国家参考标准值范围内,表明该方法准确、可靠。所测样品中含有丰富的矿质元素,栽培种Fe、Mn、Co、V、Cr等元素含量高于野生;野生和栽培菌核中Fe元素含量范围分别为31.8~108.3、49.7~805.6 mg/kg,Mn元素含量分别为5.59~35.6、12.9~67.7 mg/kg;Cu、Zn和Ba元素平均含量在1~10 mg/kg之间;Co、Li、V、As、Cd、Pb、Cr等均小于1 mg/kg,其中As(0.16 mg/kg)、Cd(0.03 mg/kg)、Pb(0.35 mg/kg)等有毒重金属均低于食品安全国家标准、世界卫生组织(WHO)和《中国药典》(2015版)最高限量。第一主成分解释原始数据变量的49.060%,Mn、Fe、V、Li、As、Cr等元素载荷值较大,茯苓中特征元素为Mn、Fe、V、Li、As、Cr。相关性分析显示14对矿质元素呈现显著相关(p0.05)或极显著相关(p0.01)。元素在茯苓生长过程中存在内在的相关关系,不同产地样品中元素含量差异显著,可能与降水、温度、生长的土壤环境和生长方式有关。     

微波消解-电感耦合等离子体质谱联用法检测岳阳市3大名优特产中金属元素含量

目的建立微波消解-电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry,ICP-MS)测定岳阳市3大名优特产中金属元素含量的分析方法。方法样品经微波消解后,采用蠕动泵在线加入内标,用ICP-MS测定岳阳的茶叶、银鱼、莲子中Pb,Cd,Cr,As,Hg 5种金属元素的含量。结果各元素在其标准曲线范围内线性关系良好,检出限为0.0003~0.010mg/kg,表明方法的灵敏度较高;各元素的加标回收率为86.4%~107.9%,相对标准偏差(relative standard deviation,RSD)为2.84%~8.97%,表明方法具有较好的准确度和精密度。按照本方法测定大虾国家标准物质(GBW10050),测量值均在标准值范围内。结论该方法快速、准确、灵敏度高,适合大批量样品的分析。     

婴幼儿辅食中有毒重金属元素测定的不确定度评定

使用电感耦合等离子体质谱(Inductively coupled plasma mass spectrometry,ICP-MS)法对婴幼儿辅食中铬(Cr)、镍(Ni)、砷(As)、镉(Cd)、铅(Pb)5种有毒重金属元素含量进行测定,并对该方法的不确定度进行评定。当婴幼儿辅食中Cr、Ni、As、Cd、Pb含量分别为0.034、0.26、0.079、0.059、0.052 mg/kg时,其扩展不确定度分别为0.003 4、0.028、0.009 6、0.007 8、0.006 0 mg/kg(置信概率为95%,k=2)。样品消解、标准溶液配制和和测量重复性为影响ICP-MS法测定婴幼儿辅食中有毒重金属元素含量准确性的关键步骤。该评定可为ICP-MS法测定婴幼儿辅食中有毒重金属元素含量的测量准确性提供参考。     

微波消解-原子荧光光谱法测定云南食用玫瑰中重金属元素

建立基于微波消解和原子荧光光谱法测定云南食用玫瑰中重金属含量的方法,考察并优化微波消解和仪器测定条件,对云南某市食用玫瑰中重金属As、Pb、Hg含量进行测定。结果表明:As、Pb、Hg元素的浓度分别在1.0μg/L～100μg/L、1.0μg/L～80μg/L、0.4μg/L～10μg/L之间呈良好线性关系,检出限分别为0.005 3、0.022 7、0.007 9μg/L,加标回收率可达90.2%～107.5%,相对标准偏差(relative standard deviate,RSD)5.0%。云南某市6个村食用玫瑰重金属As、Pb、Hg的含量分别为0.016 mg/kg～0.113 mg/kg、0.225 mg/kg～0.308 mg/kg、0.000 2 mg/kg～0.001 2 mg/kg之间,同食品安全国家标准对照,发现食用玫瑰中Pb含量存在超标情况。     

ICP-MS检测食品中铅、砷、汞、镉、钡、铬、银、镍8种有害元素

建立了电感耦合等离子体质谱法(ICP-MS)测定食品中Pb、As、Hg、Cd、Ba、Cr、Ag、Ni 8种元素的方法。样品经微波消解后,直接用ICP-MS同时测定上述8种元素,结果8种元素的检出限分别在5~200 ng/L之间;线性良好,线性相关系数均为r≥0.999 3;精密度RSD4.3%;回收率在91.44%~100.20%之间;对不同食品类型的标准物质GBW 10052(GSW-30)、GBW 10015、GBW 10018进行测定,结果令人满意。方法操作简便、分析速度快、灵敏度高,各项分析性能指标均达到要求,适用于食品中有害元素的测定。     

微波消解结合ICP-OES和ICP-MS测定奇亚籽中多种矿物质元素的含量

建立奇亚籽中K (钾)、Na (钠)、Ca (钙)、Mg (镁)、Fe (铁)、Mn (锰)、Zn (锌)、Cu (铜)、P (磷)、B (硼)、Pb (铅)、Cd (镉)、As (砷)、Cr (铬)、Al (铝)、Ni (镍)16种矿物质元素的方法。样品经微波消解,以电感耦合等离子发射光谱(ICP-OES)测定K、Na、Ca、Mg、Fe、Mn、Zn、Cu、P、B含量,电感耦合等离子质谱(ICP-MS)测定Pb、Cd、As、Cr、Al、Ni含量。结果表明,此方法的ICP-OES检出限范围在0.00850~0.10200 mg/L,定量限范围在0.0283~0.3400 mg/L;ICP-MS检出限范围在0.00471~0.11330 mg/L,定量限范围在0.0157~0.3777 mg/L。线性相关系数均为r＞0.999,加标回收率为90.4%~99.8%,相对标准偏差为0~4.1%。同时用国家标准物质大米(GBW10045(GSB-1))和小麦(GBW10011(GSB-2))评价了方法的准确性,测定结果在标准值范围内。奇亚籽中含有丰富的P、K、Ca、Mg,其中P含量最高,为6860 μg/g,Ca含量为4085 μg/g,K含量为2798 μg/g,Mg含量为2515 μg/g;Fe、Zn、Al、Mn、Cu、Na、B含量(由高到低)在5~100 μg/g。同时检测出重金属危害元素Pb、Cd、Cr、Ni,其中Pb含量符合食品安全国家标准GB 2762-2017的限量要求,未能检测出As。该方法污染小、简便、高效、准确度高,适用于奇亚籽等植物类样品中多种化学元素的测定。     

基于微波消解-电感耦合等离子体质谱法(ICP-MS)测定深海鱼肌肉中12种元素

为了建立同时测定深海鱼中硼(B)、铝(Al)、铬(Cr)、锰(Mn)、镍(Ni)、铜(Cu)、锌(Zn)、锡(Sn)、镉(Cd)、汞(Hg)、硒(Se)、铅(Pb)12种元素含量的方法,采用HNO₃-H₂O₂-H₂O消解体系,样品经微波消解,然后利用电感耦合等离子体质谱仪(ICP-MS)测定上述元素。在碰撞模式下(KED),以内标法改善基体效应及干扰。结果表明,各元素检出限低,线性关系良好,相关系数(r)在0.9991~1.0000(Hg为0.9921),检出限为0.00074~2.2 μg/kg,定量限为0.0025~7.1 μg/kg。用该方法对生物标准物质扇贝(GBW10024)进行测定,测定结果均在证书的不确定度范围以内,对带鱼样品进行加标回收率实验,加标回收率在81.8%~110.0% 之间。通过对市场上销售的不同深海鱼进行检测分析发现,受检样品安全风险较低,4种必需微量元素含量高低顺序为Zn>Se>Cu>Cr,其中Zn含量范围为3.72~22.1 mg/kg,Se含量范围为0.162~0.391 mg/kg,Cu含量范围为0.095~0.334 mg/kg,Cr含量范围为0.003~0.054 mg/kg。该方法准确可靠,灵敏度高,适合鱼肉中多元素含量的测定,为鱼肉的质量控制提供技术支持;带鱼、大黄花鱼富含微量元素Zn,小黄花鱼富含Se,是孕妇和乳母等特殊群体比较好的食物来源。     

微波消解—ICP-OES/ICP-MS法测定桂花中46种元素

为建立采用电感耦合等离子体发射光谱(ICP-OES)/电感耦合等离子体质谱(ICP-MS)测定桂花中46种元素的方法。将样品经HNO_3—H_2O_2微波消解后,以ICP-OES测定桂花中Na、Mg、Al、P、S、K、Ca和Fe,ICP-MS测定桂花中Ag、As、Ba、Cd、Co、Cr、Cs、Cu、Hg、Li、Mn、Mo、Ni、Pb、Rb、Se、Sn、Sr、Th、Ti、Tl、V、Zn和15种稀土元素。结果表明:ICP-OES检出限为0.68~18.10μg/L,ICP-MS检出限为0.001~0.093μg/L。方法精密度(RSD)为0.84%~8.42%,回收率为87.2%~113.6%。国家标准物质灌木枝叶[GBW07603(GSV-2)]的检测结果与参考值基本一致。桂花测定结果表明桂花中富含多种微量元素,其中含量在10mg/kg以上的有13种。测定的元素中含量较高的有益元素为Na、Mg、P、S、K、Ca、Fe和Zn,而含量较高的有害元素有Al、Ni、Ba和Pb。该方法具有快速、简便、准确等优点,适用于桂花中多种元素的同时测定。     

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.