超高效液相色谱-串联质谱法检测玉米油中的 黄曲霉毒素和玉米赤霉烯酮

目的建立超高效液相色谱-串联质谱法准确、快速检测玉米油中黄曲霉毒素(aflatoxins B_1、B_2、G_1、G_2)和玉米赤霉烯酮(zearalenone,ZEN)的含量,了解市售玉米油中B_1、B_2、G_1、G_2、ZEN污染状况。方法样品经乙腈:水(84:16,V:V)溶液超声离心提取后,通过多功能固相萃取柱进行净化处理,采用液相色谱-串联质谱法进行检测。结果 B_1、B_2、G_1、G_2的线性范围为0.1～20μg/L,ZEN的线性范围为3.0～200μg/L;方法回收率为74.4%～98.6%,相对标准偏差为3.9%～6.9%;B_1、B_2、G_1、G_2定量限为0.2μg/L,ZEN的定量限为6.0μg/L。市售的33份样品中,均没有检出B_1、B2、G_1、G_2;玉米赤霉烯酮检出32份,检出率为97.0%。结论该方法操作简单快速、重现性好,可用于玉米油中黄曲霉毒素和玉米赤霉烯酮的检测。     

免疫亲和净化-超高效液相色谱-串联质谱法测定食品中玉米赤霉烯酮类真菌毒素

建立食品中6种玉米赤霉烯酮类(α-玉米赤霉醇、β-玉米赤霉醇、α-玉米赤霉烯醇、β-玉米赤霉烯醇、玉米赤霉酮、玉米赤霉烯酮)真菌毒素的免疫亲和净化-超高效液相色谱-串联质谱检测的实验方法。样品经80%乙腈溶液提取,通过免疫亲和柱净化富集,用2 mL乙腈洗脱,氮吹至近干,0.5 mL 50%乙腈溶液复溶,采用超高效液相色谱-串联质谱进行测定。在ACQUITY UPLC HSS T3反相柱上分离,梯度洗脱,流动相为乙腈和水,质谱采集模式为电喷雾负离子多反应监测模式。6种目标物的线性范围为0.1~100μg/L,相关系数(R~2)均大于0.992,检出限为0.05μg/kg,定量限为0.2μg/kg,3个不同水平的加标平均回收率为73.0%~119.1%,相对标准偏差不大于10%。该方法具有操作简单、重复性好、灵敏度高、杂质干扰小等特点,可以用于食品中玉米赤霉烯酮类真菌毒素的检测。     

高效液相色谱法测定原粮中玉米赤霉烯酮的

目的 对原粮中玉米赤霉烯酮免疫亲和层析净化高效液相色谱测定方法进行改进和研究。方法 样品粉碎后经体积分数为84%的乙腈溶液超声提取, 采用免疫亲和柱净化, C18色谱柱进行分离, 以乙腈-水-甲醇(46:46:8)为流动相, 最后用高效液相色谱荧光检测器对玉米赤霉烯酮进行测定, 激发波长为274 nm, 发射波长为440 nm。结果 在优化实验条件下, 测得玉米赤霉烯酮的线性相关系数为0.9998, 相对标准偏差为5.24%～7.96%, 检出限为5μg/kg, 加标回收率为92.6%～108.0%。结论 改进后的方法适用于常用市售免疫亲和柱净化原粮中玉米赤霉烯酮。     

免疫亲和柱-高效液相色谱法测定谷物及其制品中玉米赤霉烯酮的含量

目的建立免疫亲和柱-高效液相色谱法分析检测谷物及其制品中玉米赤霉烯酮的方法。方法样品经乙腈-去离子水(84:16,V:V)提取,玉米赤霉烯酮免疫亲和柱富集净化,甲醇洗脱后,经C18反相色谱柱分离,以乙腈-水-甲醇(46:46:8, V:V:V)为流动相,使用高效液相色谱-荧光检测器检测,外标法定量。结果玉米赤霉烯酮在1～100μg/L线性范围内线性关系良好,相关系数0.9999,检出限0.8μg/kg,仪器重复测定的相对标准偏差0.19%,样品平行性测定相对标准偏差在0.10%～1.89%。检测成都市内综合农贸市场和超市内谷物及其制品中玉米赤霉烯酮的含量为1.34～43.1μg/kg,检出率为52.2%。结论该方法具有灵敏度高、重现性好、准确度高等特点,可应用于实际市场中谷物及其制品的痕量调查。     

高效液相色谱法测定原粮中玉米赤霉烯酮的改进研究

目的对原粮中玉米赤霉烯酮免疫亲和层析净化高效液相色谱测定方法进行改进和研究。方法样品粉碎后经体积分数为84%的乙腈溶液超声提取,采用免疫亲和柱净化,C18色谱柱进行分离,以乙腈-水-甲醇(46:46:8)为流动相,最后用高效液相色谱荧光检测器对玉米赤霉烯酮进行测定,激发波长为274 nm,发射波长为440 nm。结果在优化实验条件下,测得玉米赤霉烯酮的线性相关系数为0.9998,相对标准偏差为5.24%~7.96%,检出限为5μg/kg,加标回收率为92.6%~108.0%。结论改进后的方法适用于常用市售免疫亲和柱净化原粮中玉米赤霉烯酮。     

北京地区部分市售食用植物油中玉米赤霉烯酮和脱氧雪腐镰刀菌烯醇的污染状况分析

目的分析北京市售植物油中玉米赤霉烯酮和脱氧雪腐镰刀菌烯醇的污染状况。方法实验采用同位素稀释-超高效液相色谱-串联质谱法,在多反应监测模式下对所采集玉米油、花生油、调和油等食用油样中的玉米赤霉烯酮(ZEN)、脱氧雪腐镰刀菌烯醇(DON)进行了检测,并对其污染现状进行分析。结果 ZEN和DON在3~500 ng/mL浓度范围内线性良好,相关系数为0.999,加标回收率为95.05%~107.10%,ZEN和DON方法的检出限分别为0.03μg/kg和0.9μg/kg;ZEN和DON方法的定量限分别为0.1μg/kg和3μg/kg。对北京市售30个油样检测结果表明,DON为未检出,ZEN检出率为100%,最高含量为333μg/kg,最低含量为1.95μg/kg,平均含量为67.7μg/kg,低于欧盟规定的限量标准400μg/kg。结论通过分析食用油中真菌毒素的含量状况,初步了解了北京市售植物油中玉米赤霉烯酮和脱氧雪腐镰刀碱烯醇的污染状况。     

液相色谱-串联质谱法测定粮食中的玉米赤霉烯酮

目的应用液相色谱-串联质谱法建立粮食中玉米赤霉烯酮的检测方法,并对宁夏市售小麦粉和玉米制品进行分析。方法样品经乙腈-水(84∶16,V/V)提取,Pribo Fast 226多功能净化柱净化;以甲醇-10 mmol/L乙酸铵水溶液为流动相梯度洗脱,用Atlantis T3色谱柱分离,以电喷雾负离子模式进行质谱测定。结果分别以小麦粉和玉米制品为加标基质,3个加标水平下玉米赤霉烯酮的平均回收率为85.4%~93.7%,RSD9.0%,检出限(S/N=3)为0.08μg/kg,定量限(S/N=10)为0.2μg/kg。结论该方法操作快速简单、重现性好,可用于粮食中玉米赤霉烯酮的检测。     

超高效液相色谱-三重四级杆质谱串联法测定粮谷中的玉米赤霉烯酮类真菌毒素的研究

建立了粮谷中玉米赤霉烯酮、α-玉米赤霉烯醇、β-玉米赤霉烯醇检测的超高效液相色谱-三重四级杆质谱串联的分析方法。样品经0.1%甲酸水-乙腈溶液提取,经免疫亲和柱净化,以水溶液(含0.1%甲酸)和甲醇(含0.1%甲酸)为流动相进行梯度洗脱,质谱以负离子模式扫描和多反应监测模式进行检测,以外标法定量。结果表明,玉米赤霉烯酮、α-玉米赤霉烯醇、β-玉米赤霉烯醇在1~100μg/L浓度范围内呈现良好的线性关系,线性相关系数均大于0.994,检出限为0.5~1.0μg/kg,在5、20、80μg/kg 3个添加水平下,平均加标回收率为87.2%~100.6%,相对标准偏差为3.2%~6.4%。本方法结果准确可靠,灵敏度高,可适用于粮谷中玉米赤霉烯酮类真菌毒素的检测。     

QuEChERS-高效液相色谱-串联质谱法检测奶粉中玉米赤霉烯酮及其代谢物

建立了QuEChERS-高效液相色谱-串联质谱同时检测奶粉中玉米赤霉烯酮及其代谢产物的检测方法。样品用10 mL超纯水溶解,1%乙酸乙腈溶液提取,乙酸钠盐析,C₁₈、N-丙基乙二胺(primary secondary amine,PSA)和无水硫酸镁净化,在ZORBAX SB-C₁₈色谱柱上分离,以5 mmol/L乙酸铵溶液和乙腈作为流动相进行梯度洗脱,ESI负离子模式扫描,多反应监测(MRM)测定,β-玉米赤霉烯醇内标法定量分析。奶粉中玉米赤霉烯酮及其代谢产物在0.1~50 μg/L浓度范围内呈线性关系,相关系数均高于0.999,基质效应为抑制效应;检出限(LOD)均为0.1 μg/kg,定量限(LOQ)均为0.2 μg/kg。奶粉中玉米赤霉烯酮及其代谢产物的3个加标浓度水平的平均回收率范围为85.2%~119.3%,相对标准偏差(RSD)在0.3%~12.2%(n=7)之间。该方法简便快速、准确可靠,可用于检测奶粉中玉米赤霉烯酮及其代谢物。     

高效液相色谱法对玉米中玉米赤霉烯酮的测定

研究了高效液相色谱法测定玉米中玉米赤霉烯酮的方法.样品借鉴了GB/T 19540-2004中提取玉米赤霉烯酮的方法,通过Oasis HLB净化柱对提取液净化,以agilent extent C18色谱柱为分离柱,乙腈-水(V水:V乙腈=55:45)为流动相进行荧光检测(λex=235 nm,λem=460 nm).玉米赤霉烯酮的质量浓度在12～2 400μ/kg范围内呈良好线性,相关系数为0.9994,对添加高、中、低3个浓度玉米赤霉烯酮的玉米样品进行加标回收试验,平均回收率分别为96.736%、93.839%、86.240%,变异系数在1%～10%之间,最低检测限为10μ/kg.此方法对玉米中玉米赤霉烯酮的检测是可行的,且可给谷物中玉米赤霉烯酮检测方法优化提供参考.     

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.