HPLC法测定酸奶饮料中的磺胺抗生素

研究了酸奶饮料中磺胺嘧啶和磺胺甲唔唑的高效液相色谱法.采用C18柱;流动相为甲醇:0.08%乙=45:55;柱温25℃:检测波长263 nm;流速0.8 mL/min. 结果表明两种磺胺药物在0.05～lmg/L的范围内线性良好,回收率为97.4%～101.9%.本方法具有灵敏度高,重复性好等特点,可准确测定酸奶锨料中两种磺胺类药物的含量.     

免疫亲和柱净化-柱后光化学衍生-高效液相色谱法检测粮油中黄曲霉毒素

介绍了同时采用免疫亲和柱净化-柱后光化学衍生-高效液相色谱方法检测粮油中黄曲霉毒素B1、B2、G1和G2。样品经过甲醇-水(体积比为70∶30)提取,通过免疫亲和柱富集和净化,采用Cloversil C18色谱柱(4.6 mm i.d.×150 mm,粒度5μm),以甲醇∶水(50∶50)溶液为流动相,柱后光化学衍生、利用荧光检测器检测,黄曲霉毒素B1、B2、G1和G2检出限分别为0.5,0.2,0.7和0.2μg/kg,标准曲线的线性范围分别为:0.51～10.19 ng/mL,0.15～2.92 ng/mL,0.54～10.71 ng/mL,0.16～3.3 ng/mL,在稻谷、食用油样品中,平均加标回收率为70.3%～109.8%,相对标准偏差为1.4%～9.1%,说明回收率、精密度均可以满足实际工作的要求。     

固相分散萃取-液相色谱法测定豆沙中的富马酸二甲酯

采用固相分散萃取技术对豆沙样品进行预处理,用高效液相色谱法测定其中的富马酸二甲酯。Diamonsil C18色谱柱,柱温25℃,甲醇-水（体积比为55∶45）作流动相,流速1.0mL/min,检测波长220nm。富马酸二甲酯在0.136μg/mL～33.5μg/mL范围内线性良好,相关系数为0.9998,方法检出限0.82μg/g,平均回收率82.5%,相对标准偏差为3.3%。市售豆沙馅中未检出富马酸二甲酯。     

利用高效液相色谱法测定雨生红球藻中虾青素含量

利用高效液相色谱法对雨生红球藻中的虾青素含量进行了测定。色谱柱为KromasilC18柱(250×4.6mm),流动相为二氯甲烷∶甲醇∶乙腈∶水=5∶85∶5∶5,流速1mL/min,检测波长480nm,柱温25℃。虾青素在1.896～18.96μg/mL范围内线性关系良好,r=0.9999,RSD=1.12%(n=6),回收率为99.69%～102.6%。本方法简便快速,定量准确,重现性好。     

高效液相色谱法测定酸汤中的有机酸

建立了高效液相色谱法快速测定酸汤中五种有机酸的方法,在C18反相色谱柱,紫外检测器(波长210nm),0.01mol/L磷酸二氢铵缓冲溶液(pH 2.6)∶甲醇为95∶5作为流动相洗脱,流速为1.0mL/min,柱温为25℃的色谱条件下,同时分析酸汤中5种有机酸,有机酸标准曲线相关系数均在0.9970～0.9985之间,回收率在90.5%～97.6%之间,方法检出限0.1～0.3μg/mL,相对标准偏差为0.7%～3.1%。该方法具有操作简单、重复性好、准确度高的特点。     

高效液相色谱法测定豆粕中异黄酮含量的研究

介绍了高效液相色谱同时测定豆粕中4种大豆异黄酮的方法。确定出色谱条件为:色谱柱HypersilODS2C18柱(250mm×4.6mmID,5μm),流动相甲醇∶水=40∶60,柱温3O℃,流速1.0mL/min,检测波长260nm。大豆苷、染料木苷、大豆苷元、染料木素在0.21～8.56μg/mL范围内浓度与峰面积具有很好的线性关系,相关系数r为0.999155～0.999991。该测定方法的回收率大于99%,变异系数小于3%。     

高效液相色谱法快速测定乳粉中叶黄素的质量分数

建立一种测定配方奶粉中叶黄素质量分数的高效液相色谱方法。采用Diamonsil C18色谱柱(5μm,250 mm×4.6 mm),流动相为甲醇-水(97∶3),流速1.0 mL/min,检测波长445 nm,采用空白基质加标实验绘制标准曲线,该方法在0.5～100 mg/L的质量浓度范围内线性关系良好(R=0.9987),加标水平为0.50,1.00,5.00μg/g时,回收率分别介于96.8%～98.4%之间,相对标准偏差介于4.27%～6.73%之间,该方法检测限低于0.10μg/g。该方法操作简便,灵敏度高、准确度高、重现性好,适合于配方奶粉中叶黄素的测定。     

HPLC-MS/MS法测定安神类代用茶中19种镇静安神类非法添加物质

建立奶粉中地塞米松的高效液相色谱-质谱/质谱测定方法。样品经甲酸乙腈溶液超声提取,经Oasis PRiME HLB固相萃取柱净化后上样。色谱条件采用Waters XBridge C18柱(2.1 mm×150 mm,5μm),流动相为0.1%甲酸水溶液-乙腈梯度洗脱,流速为0.3 mL/min,柱温40℃,采用电喷雾正离子扫描模式。结果表明:该物质检出限为1.0μg/kg,定量限为3.0μg/kg,线性范围:0～20 ng/mL。加标回收率为90.7%～98.9%。该方法操作简单高效,重现性较好,适用于奶粉中地塞米松含量的测定。     

微萃取瓶富集-液相色谱法测定苹果醋中氨基甲酸酯类农药

采用自制微萃取瓶富集—高效液相色谱法测定苹果醋中氨基甲酸酯类农药。异辛烷作萃取剂,反相C18色谱柱,V(甲醇)∶V(乙腈)∶V(水)=40∶17∶43做为流动相,流速1.0 mL/min,210 nm紫外检测。采用基质校正工作曲线,西维因、抗蚜威、叶蝉散和仲丁威在16～1 000 ng/mL内线性良好。平均回收率分别为86.33%、101.22%、100.17%和112.32%,相对标准偏差小于5.26%。     

高效液相色谱法测定饮料中的咖啡因含量

咖啡因是咖啡饮料、茶饮料和可乐等饮料中的主要成分,也是中枢神经系统的兴奋药。本文建立了高效液相色谱测定饮料中咖啡因含量的方法,色谱柱为反相ODS C18柱,甲醇—水溶液为流动相进行洗脱。结果表明,在柱温35℃,甲醇∶水为1∶1,流速1.0mL/min,检测波长272nm条件下,咖啡因的浓度在0.1～70.0mg/L范围内与峰面积成良好的线性关系,回收率为79.79%～101.56%,精密度RSD在0.11%～1.38%。该方法可快速、准确地测出各种市售饮料中咖啡因的含量。     

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.