QuEChERS-高效液相色谱-串联质谱法测定春笋中4种农药残留

目的建立检测春笋中吡虫啉、茚虫威、辛硫磷和克百威4种农药的QuEChERS-高效液相色谱-串联质谱法。方法前处理采用QuEChERS方法,乙腈为提取液,N-丙基乙二胺(PSA)为净化剂,结合液相色谱-质谱联用技术,正离子多反应监测(MRM)模式进行检测,外标法定量。结果吡虫啉、茚虫威、辛硫磷和克百威4种农药在0.5～20.0 ng/ml范围呈良好的线性关系,相关系数(r~2)均大于0.991,在4～40μg/kg加标范围内,4种农药的回收率为72.4%～92.8%,精密度为1.5%～9.2%,方法的检出限为0.4μg/kg,定量限为1.2μg/kg。结论建立了适用于检测春笋中吡虫啉、茚虫威、辛硫磷和克百威4种农药的QuEChERS-高效液相色谱-串联质谱法,该方法准确、灵敏、高效、简便。     

UPLC-MS/MS检测果蔬饮料中痕量吡虫啉

建立一种快速、有效的超高效液相色谱-串联质谱法测定果蔬饮料中痕量吡虫啉农药残留的方法。样品经0.1%醋酸-乙腈提取后,采用氨基固相萃取小柱进行净化和富集。采用Waters Atalantis T3色谱柱(2.1 mm×150 mm,3μm)分离,以0.1%甲酸-乙腈为流动相的梯度洗脱模式下,吡虫啉标准在0.5 ng/mL~50.0 ng/mL浓度范围内线性良好,相关系数r~2为0.999,检出限为0.15μg/kg,定量限为0.50μg/kg,加标回收率达到93.2%~96.9%。     

超高效液相色谱-串联质谱法测定茶叶中6种农药残留

目的建立超高效液相色谱-串联质谱法测定茶叶中吡虫啉、多菌灵、啶虫脒、水胺硫磷、三唑磷和甲基异柳磷6种农药残留的方法。方法样品经乙腈提取,NH_2固相萃取小柱富集、净化,以二氯甲烷-甲醇(9:1,V:V)为洗脱溶液;样品经浓缩定容后,采用Thermo C_(18)(2.1 mm×50 mm,1.7μm)色谱柱分离,流速为0.3 mL/min,以水-甲醇-乙腈为流动相进行梯度洗脱,采用超高效液相色谱-串联质谱法多反应监测模式进行测定,采用基质标准溶液外标法定量。结果 6种农药在0.005~0.25μg/mL浓度范围内呈良好的线性关系,相关系数为0.9973~0.9998。当添加水平为0.005、0.025、0.25 mg/kg时,6种农药在茶叶中的加标回收率为72.4%~106.6%,相对标准偏差为1.6%~10.0%。方法定量限为0.5~5μg/kg。结论该方法操作简单、快速,可适用于茶叶中吡虫啉、啶虫脒、多菌灵、水胺硫磷、三唑磷和甲基异柳磷6种农药残留的测定。     

UPLC-MS/MS法同时测定蔬菜中34种农药残留

采用超高液相色谱-串联质谱联用仪(UPLC-MS/MS)技术建立了同时检测蔬菜中34种农药多残留量的快速检测方法。样品经乙腈提取,浓缩定容后用Qu ECh ERS农残净化管净化,Acquity BEH-C18超高液相色谱柱分离,进入电喷雾串联四极杆质谱进行检测,采用多反应监测(MRM)分析,对液质分离条件进行优化。结果表明34种农药在10 ng/m L~200 ng/m L范围内线性良好(r≥0.993 6)。在10μg/kg~30μg/kg范围内,平均加标回收率在68.7%~116.8%之间,RSD≤12%。该方法检出限为0.001 mg/kg~0.01 mg/kg,测定结果满足蔬菜样品中多残留农药的检测要求。     

食品中黄曲霉毒素B_1的液相色谱-串联质谱测定法

建立了食品中黄曲霉毒素B1残留量的超高效液相色谱-串联质谱的检测方法。样品经乙腈+水(84+16)提取后,经多功能净化柱净化,超高效液相色谱-串联质谱法检测。本方法定量限为1μg/kg,线性范围为1~20 ng/mL;在黄曲霉毒素B1添加水平为1~10μg/kg时,在玉米样品中的回收率为95%~105%;在酱油样品中的回收率为96%~106%。     

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。     

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。     

QuEChERS-高效液相色谱-串联质谱法测定牛奶中氨基甲酸酯类农药残留量

目的建立高效液相色谱-串联质谱法(high performance liquid chromatography-tandem mass spectrometry,HPLC-MS/MS)测定牛奶中5种氨基甲酸酯类农药的方法。方法样品经乙腈提取、氮吹浓缩、QuEChERS净化,高效液相色谱-串联质谱法测定,采用外标法定量。结果5种氨基甲酸酯类农药在2.00-200μg/kg范围内线性关系良好(r>0.999);方法检出限为0.50~3.00μg/kg,定量限为1.50~10.00μg/kg;加标水平为0.010~0.050 mg/kg时,回收率为83.6%-108%,相对标准偏差为1.6%~15.6%。结论该方法简便快捷、灵敏度高,适用于牛奶中氨基甲酸酯类农药的检测。     

固相萃取净化高效液相色谱法测定玉米中吡虫啉

研究采用固相萃取-高效液相色谱法测定玉米中吡虫啉的残留。样品中吡虫啉经乙腈提取,采用刚活化后弗罗里硅土对其进一步净化提纯,洗脱液为丙酮;将洗脱液用氮吹浓缩、定容、过滤后,供液相色谱测定;采用安捷伦XDB-C18(250mm×4.6mm)色谱柱,柱温40℃,甲醇-乙腈-水(10∶10∶80)为流动相,检测波长270nm;该方法的检测限为0.2μg/mL,线性范围0.2～5μg/mL,线性相关系数为0.9993,回收率达84.2%。结果表明,该分析方法不仅操作简便,分析周期短,而且方法准确度高,色谱分离效果好。     

超高效液相色谱-串联质谱法同时测定梨中22种农药残留

目的建立一种超高效液相色谱-串联质谱法测定梨中苯酰菌胺、吡蚜酮、氟虫脲等22种农药残留的分析方法。方法样品经过高速匀浆后加入乙腈进行提取,采用ReproSil 100 C_(18)柱(150 mm×2.1 mm, 5μm),流速为0.3mL/min,柱温为35℃进行分离,应用超高效液相色谱-串联质谱正离子模式下的多反应监测(multiple reaction monitoring, MRM)扫描进行定性定量分析。结果在浓度测定范围0.010～0.20 mg/L内, 22种农药均成线性关系,相关系数(r~2)为0.9709～0.9998。在0.010、0.050、0.10 mg/kg 3个添加水平下, 22种化合物的回收率为71.4%～106.7%,相对标准偏差为0.7%～9.9%;检出限为0.90～4.6μg/kg,方法定量限3.0～15.4μg/kg。在实际梨样品检测到5种农药残留。结论此方法简便快速、准确度高,可用于梨样品中22种农药残留的测定。     

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.