分子印迹柱净化-UPLC-MS/MS测定果蔬制品中展青霉素

建立分子印迹亲和柱净化-超高效液相色谱串联质谱检测果蔬制品中展青霉素的方法。样品经2.5%乙酸水提取,分子印迹亲和柱净化,超高效液相色谱串联质谱测定,外标法定量。展青霉素在2.0 ng/mL~50.0 ng/mL范围内线性良好(R2≥0.999 8),方法的检出限为2.0μg/L。在添加水平为5.0和50.0μg/L时,4种果蔬制品回收率为78.4%~92.0%,相对标准偏差低于7.2%。该方法准确、稳定、灵敏,能够满足果蔬制品中展青霉素检测与确证的需要。     

液相色谱-串联质谱法测定禽蛋中β-内酰胺类药物残留

目的 建立了禽蛋中普鲁卡因青霉素、青霉素V、青霉素G、氨苄西林、氯唑西林、阿莫西林、头孢氨苄、头孢噻呋、头孢喹肟药物残留检测的液相色谱-串联质谱方法。方法 禽蛋用80%乙腈水溶液提取,PRiME HLB固相萃取小柱净化,用液相色谱-串联质谱测定,青霉素G-D7内标法定量。结果 在0.5-20μg/L的基质匹配标准溶液内9种β－内酰胺类药物均呈良好线性关系,相关系数均大于0.994。样品中9种β－内酰类药物的定量限为1μg/kg,在1μg/kg～10μg/kg的添加浓度范围内平均回收率为73%～96%,相对标准偏差(RSD)小于10%。本方法方便快捷准确,适于禽蛋中的9种β－内酰胺类药物残留检测。     

高效液相色谱-串联质谱法测定牛奶和奶粉中9种青霉素类药物残留量

建立一种检测牛奶和奶粉中9种青霉素类药物残留量的高效液相色谱-串联质谱方法。样品经乙腈-水提取,经HLB固相萃取柱净化,用高效液相色谱串联质谱检测,外标法定量。本方法的检出限,牛奶中氨苄西林、奈夫西林为1μg/kg,阿莫西林、哌拉西林、青霉素G、青霉素V、氯唑西林为2μg/kg,苯唑西林、双氯西林为4μg/kg;奶粉中氨苄西林、奈夫西林为8μg/kg,阿莫西林、哌拉西林、青霉素G、青霉素V、氯唑西林为16μg/kg,苯唑西林、双氯西林为32μg/kg。9种青霉素在1.0～50ng/mL范围呈良好线性,线性相关系数大于0.9888。牛奶的平均回收率为77.58%～97.77%,测定结果的相对标准偏差为4.24%～16.59%(n=10);奶粉的平均回收率在85.95%～96.78%之间,相对标准偏差为2.71%～13.41%(n=10)。该方法具有简便、快速、准确度高、检出限低的优点,适用于牛奶和奶粉中青霉素类抗生素的测定。     

液相色谱-串联质谱法测定河豚鱼和鳗鱼中9种青霉素类抗生素

目的建立高压液相色谱-电喷雾串联质谱(HPLC-MS-MS)同时测定河豚鱼和鳗鱼中9种青霉素残留量的检测方法。方法样品经乙腈-氨水溶液提取后,用C18色谱柱分离,乙腈-乙酸为流动相梯度洗脱,最后采用液相色谱-电喷雾串联质谱在正离子多反应监测模式下测定。结果在1.0～20μg/kg(LOQ～10LOQ)范围时,方法线性关系良好,相关系数大于0.999。在LOQ、2LOQ、4LOQ、10LOQ四个添加水平下青霉素的回收率在81.4%～109.7%之间,相对标准偏差在2.81%～7.12%之间,方法检出限是:萘夫西林、青霉素G、哌拉西林、青霉素V、苯唑西林为1.0μg/kg;阿莫西林、氨苄西林、氯唑西林、双氯西林为2.0μg/kg。结论此方法灵敏度高,准确性好,适用于水产品中青霉素的定量检测。     

分子印迹固相萃取-高效液相色谱法测定果汁中的展青霉素

建立了分子印迹固相萃取-高效液相色谱法测定果汁中展青霉素的方法。浓缩果汁样品经酶解,乙酸-水溶液稀释,分子印迹固相萃取小柱净化后(澄清果汁样品经乙酸-水溶液稀释后,直接进行SPE净化),以Waters XSELECT HSS T3色谱柱为分离柱,以水和乙腈作为流动相,二极管阵列检测器高效液相色谱进行检测,外标法定量。展青霉素在20～1000μg/L质量浓度范围内线性关系良好,相关系数为0.9994,方法的定量限为10.0μg/kg;添加水平为10.0、20.0μg/kg和40.0μg/kg时,加标回收率为83.0%～91.5%,相对标准偏差为2.8%～7.6%。结果表明:该方法准确、高效、特异性好、重现性高,适用于果汁中展青霉素的测定。     

高效液相色谱串联质谱法测定蔬果中啶酰菌胺和环酰菌胺残留

建立蔬菜和水果中啶酰菌胺和环酰菌胺的高效液相色谱串联质谱检测方法。将试样中残留的啶酰菌胺和环酰菌胺用含1%乙酸的乙腈溶液均质提取,提取液混合使用乙二胺-N-丙基硅烷和十八烷基硅烷键合相基质分散净化,用高效液相色谱串联质谱检测和确证,外标法定量;方法通过空白基质溶液稀释标准建立校正的标准曲线,以消除基质效应。结果表明：啶酰菌胺和环酰菌胺在1～100μg/L范围内具有良好的线性关系,相关系数分别为0.9996和0.9997;在5～50μg/kg范围内,平均添加回收率在77.7%～93.8%之间,相对标准偏差在2.1%～6.3%之间。啶酰菌胺和环酰菌胺方法定量限分别为1.32μg/kg和1.20μg/kg,检出限分别为0.395μg/kg和0.361μg/kg。     

超高效液相色谱-质谱法测定果酱中纳他霉素残留

目的建立了果酱中纳他霉素的超高效液相色谱-串联质谱(UPLC-MS/MS)检测方法。方法样品加入0.5g氯化钠、经10ml丙酮萃取,以甲醇-水溶液为流动相进行梯度洗脱,经BEHC18色谱柱分离,通过多反应监测模式(MRM)进行测定。结果纳他霉素在蓝莓果酱、葡萄树莓果酱、香蕉草莓果酱、黄桃果酱、苹果果酱和山楂草莓果酱中的线性范围分别为0.5～25.0、0.5～25.0、1.0～25.0、1.0～25.0、0.5～25.0和1.0～25.0μg/kg,相关系数(R2)均大于0.99。6种果酱中目标化合物的定量限为0.5～1.0μg/kg,3个浓度水平的加标回收率为80.1%～113.3%,相对标准偏差(RSD,n=5)小于20%。结论该方法快速、准确、操作简便,可用于果酱中纳他霉素的确证和定量分析。     

超高效液相色谱串联质谱法测定鸡肝脏中的马杜霉素

本文采用超高效液相色谱-串联质谱法测定鸡肝脏中的马杜霉素残留。样品以乙腈提取,经HLB固相萃取柱净化,超高效液相色谱-串联质谱检测。方法定量限2μg/kg,线性范围2～100μg/m L;在马杜霉素添加水平为2～10μg/kg时,鸡肝脏中马杜霉素回收水平在78.5%～108.6%,方法稳定可靠,适合相应鸡肝脏产品的马杜霉素检测。     

液相色谱法及液相色谱-串联质谱法测定山楂及其制品中展青霉素的结果比较与建议

目的比较液相色谱法(liquidchromatography,LC)和液相色谱-串联质谱法(liquid chromatography-tandem mass spectrometry, LC-MS/MS)测定山楂及其制品中展青霉素的方法学指标。方法 LC法:山楂及固体制品经粉碎酶解后,用乙酸乙酯提取,Mycosep?228Aflapat净化柱净化浓缩,以乙腈和水作为流动相进行梯度洗脱,液相色谱仪被测定; LC-MS/MS法:样品处理方法同LC法(除加同位素外),以乙腈和水作为流动相进行梯度洗脱,外标法定量,采用电喷雾离子源负模式测定。结果 LC法和LC-MS/MS法展青霉素在10～200 ng/mL浓度内线性良好,相关系数均大于0.9999; LC法的回收率为96.12%～104.20%, RSD均小于2.5%,检出限为0.52～0.63μg/kg,定量限为1.7～2.0μg/kg; LC-MS/MS法的回收率为94.68%～103.59%, RSD均小于2.5%,检出限为0.12～0.39μg/kg,定量限为0.38～1.29μg/kg。结论 2种方法结果无显著差异,均可适用于山楂及山楂制品中展青霉素的测定。     

超高效液相色谱-串联质谱法测定鸡肉、鸡蛋中氟苯尼考和氟苯尼考胺残留

目的建立超高效液相色谱-串联质谱准确测定鸡肉、鸡蛋中氟苯尼考和氟苯尼考胺残留的分析方法。方法鸡肉和鸡蛋样品加入D5-氯霉素内标,经氨化乙酸乙酯混合溶液超声离心提取,提取液减压蒸馏浓缩后,C18固相萃取柱净化处理,采用超高效液相色谱-串联质谱法对氟苯尼考和氟苯尼考胺同时进行检测。结果氟苯尼考线性范围为0.2～20μg/L,检出限为1.0μg/kg,定量限为3.0μg/kg,方法回收率为88.0%～108.0%,相对标准偏差为4.7%～6.4%;氟苯尼考胺线性范围为0.2～20μg/L,检出限为1.0μg/kg,定量限为3.0μg/kg,方法回收率为76.0%～93.1%,相对标准偏差为4.1%～7.2%。结论本方法精确、重现性好,适用于鸡肉、鸡蛋中氟苯尼考和氟苯尼考胺残留量的测定。     

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.