水产品中三聚氰胺的快速检测方法

建立高效液相色谱法快速检测水产品中三聚氰胺的方法。样品采用50%甲醇水+1%三氯乙酸(3+1)振荡提取,高速离心后过滤进行HPLC测定。三聚氰胺在0.2μg/mL～10.0μg/mL浓度范围内线性关系良好,相关系数0.9989,加标水平在0.5mg/kg～10mg/kg范围内,回收率为85%～91%,相对标准偏差4.2%～6.4%,方法的检出限为0.5mg/kg。该方法与固相萃取前处理方法相比,过程简便、快速准确。     

大米蛋白粉中三聚氰酸及其类似物的硅烷衍生化GC-MS检测方法研究

建立一种简单、快速、准确同时测定大米蛋白粉中三聚氰胺及其类似物三聚氰酸、三聚氰胺一酰胺、三聚氰胺二酰胺的方法。样品经二乙胺- 水- 乙腈(1:4:5,V/V)超声提取30min 后,提取液于70℃条件下氮气吹干,在吡啶介质中经甲基硅烷化衍生后采用气相色谱- 质谱仪测定(内标法定量)。此方法检测限为0.5mg/kg、线性相关系数(20～1000μg/L 范围内)不小于0.9989;当加标量为1.0～5.0mg/kg 时,平均回收率为72.01%～96.45%、相对标准偏差不大于6.3%。此方法可用于大米蛋白粉中三聚氰酸及其类似物的检测。     

高效液相色谱法测定植物性样品中三聚氰胺的含量

建立了高效液相色谱法检测植物性样品中三聚氰胺的方法.样品由1%三氯乙酸-乙腈超声提取,加入蛋白沉淀剂进行纯化.色谱柱ZORBAX SB-Aq(250 mm × 4.6 mm,5 μm),流动相为磷酸-三乙胺溶液,流速为0.6 mL/min检测波长为240 nm,回收率为89.8%～91.1%,相对标准偏差在0.75%～1.60%之间.     

高效液相色谱法测定肠衣中三聚氰胺

建立了用酸性氧化铝脱脂、固相萃取净化与高效液相色谱测定肠衣中三聚氰胺的检测方法.试样用三氯乙酸溶液-乙腈超声提取,酸性氧化铝脱脂后经阳离子交换固相萃取柱净化,用高效液相色谱测定,光谱定性、外标法定量.方法的线性范围为1～100mg/L ,相关系数为0.9999,检出限(S/N=10)均达到1mg/kg,在三个浓度水平(1, 5,10mg/kg)进行精密度和回收率试验,所得相对标准偏差在3.3%～4.8%之间,回收率在80%～110%之间.     

高效液相色谱法快速测定乳粉中的三聚氰胺与双氰胺

建立高效液相色谱-二极管阵列检测器同时检测乳粉中三聚氰胺和双氰胺的分析方法。采用1%三氯乙酸溶液提取样品中的三聚氰胺和双氰胺,氨基柱为分析柱,流动相为乙腈-水（75∶25,V/V）,流速1.0 mL/min,检测波长233 nm。2 种物质在0.005～60 mg/L范围内与其峰面积线性关系良好,不同添加水平的回收率在83.2%～102.6%,三聚氰胺和双氰胺的方法定量限分别为0.17、0.15 mg/kg,方法变异系数为2.3%～7.2%（n=6）。此方法操作简便、快速、成本低,适用于乳粉中三聚氰胺和双氰胺的同时检测。     

离子交换色谱-二极管阵列检测法测定食品中三聚氰胺

样品经l%三氯乙酸提取,离子交换色谱柱分离,二极管阵列检测器进行检测。实验结果表明,三聚氰胺在(0.1～10.0)μg/mL时,线性关系良好(r>0.999),在(2.5～250)mg/kg的添加水平范围内的平均回收率为98.9%～104.3%,相对标准偏差(RSD)为0.4%～4.8%,方法的检出限为1.0 mg/kg。方法简单、准确,适合食品中三聚氰胺的检测。     

固相萃取-离子交换色谱法测定饲料中的三聚氰胺

建立了饲料中三聚氰胺的固相萃取-离子交换色谱检测方法.饲料样品经0.1 mol/L的盐酸溶液提取,OASIS MCX固相萃取柱净化,以pH值为3.0的0.05 moL/L磷酸二氢钾一乙腈(体积比为70:30)为流动相,Agilent ZORBAX 300-SCX离子交换色谱柱分离,二极管阵列检测器240 mm检测.该方法线性范围为0.1～5.0μg/ml,定量检出限为2.0 mg/kg,相对标准偏差为2.45%～4.15%,加标回收率为92.0%～95.5%.     

基质固相分散—高效液相色谱法测定蜂蜜中三种酚类化合物

采用基质固相分散技术处理样品、反相高效液相色谱法同时测定蜂蜜中三种酚类化合物.Diamonsil C18柱,甲醇-水(体积比为45:55)流动相,检测波长275 nm.在0.04 mg/L～16.3 mg/L范围内3组分线性关系良好.方法检出限分别为0.05 mg/kg～0.06 mg/kg.回收率范围:86.88%～90.88%.相对标准偏差分别为2.25%、2.31%、2.48%.     

超高效液相色谱法测定动物源性食品中的三聚氰胺

建立动物源性食品中三聚氰胺含量测定的超高效液相色谱法。鸡蛋样品用1% 三氯乙酸- 乙腈(3:1,V/V)溶液提取、离心、固相萃取柱净化,然后采用CR 色谱柱(阳离子交换填料SCX 与C18 包被型填料按质量比1:4 混合)进行超高效液相色谱分析。兔肉样品用乙腈提取,离心后以强阳离子色谱柱进行超高效液相色谱分析。对色谱条件进行优化,选用236nm 作为检测波长,鸡蛋中三聚氰胺在浓度为1.00～5.00mg/L 的范围内线性关系良好,在添加浓度为1.00、2.00、5.00mg/kg 时,添加回收率在89.24%～91.06% 之间,RSD 小于6.00％。对于兔肉中三聚氰胺浓度在0.4～4mg/L 的范围内线性良好,在添加浓度为2.00、5.00、10.00mg/kg 时,添加回收率在82.65%～86.54% 之间,RSD 小于7.50%。该方法简便、快速,检测灵敏度、准确度及精密度均满足检测要求。     

气相色谱法检测西红柿和白梨中嘧菌酯残留

建立了气相色谱法检测西红柿和白梨中嘧菌酯残留的快速分析方法.样品用乙酸乙酯 环己烷(1 1)超声波萃取,气相色谱-电子捕获检测法测定.实验结果表明,嘧茵酯在0.005mg/kg～1.0mg/kg浓度范围内呈线性,其相关系数r＞0.99.在低、中、高3个添加水平,嘧茵酯的回收率为85%/110.5%,相对标准偏差为3.89～114%检测限为0.01mg/kg.     

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.