高分辨质谱库和特征组分诊断比值法快速鉴别食品中非法添加淫羊藿

建立了一种基于高分辨质谱库和特征组分诊断比值法鉴别食品中非法添加淫羊藿的方法。采用高效液相色谱-四极杆-飞行时间质谱仪构建淫羊藿6种特征组分高分辨质谱库进行初步筛查,将不同产地和采摘时间的淫羊藿中药材模拟配制酒、代用茶和饮料样品,构建3种基质中淫羊藿特征组分液相色谱分析方法,选取受产地、采摘时间、加工工艺等影响较小,不同基质组间无显著性差异的3组特征组分峰面积诊断比值DR1(朝藿定A/朝藿定B)、DR3(朝藿定A/淫羊藿苷)和DR7(朝藿定B/淫羊藿苷),合并后绘制箱图确定各诊断比值非异常值范围分别为0.60~0.96、0.26~0.64和0.35~0.91,以此作为鉴别指标。对实际样品配制酒、代用茶及饮料进行分析,1批次配制酒样品与淫羊藿6种特征组分高分辨质谱库匹配一致,且3组特征组分诊断比值DR1、DR3、DR7分别为0.73、0.28、0.38,均在规定区间内,推断该配制酒样品中加入了淫羊藿中药材。该方法准确、快捷、稳定性好,可快速鉴别食品中非法添加淫羊藿,为打击食品中非法添加淫羊藿违法行为提供技术支撑。     

液相色谱串联质谱法测定食品中淫羊藿苷等20种功能成分

采用超高效液相色谱—串联质谱仪建立了配制酒、饮料及代用茶中淫羊藿苷、金丝桃苷、补骨脂素等20种功能成分定量的检测方法。样品经甲醇—水溶液提取后,稀释净化,提取液离心,过滤,上机测定,Thermo Acclain RSLC C18(2.6μm,2.1mm×100mm)色谱柱进行分离,乙腈和水为流动相梯度洗脱,电喷雾正、负离子多反应监测扫描(MRM)模式下进行测定,外标法定量。20种化合物的线性检测范围最高浓度为500ng/mL,相关系数R2>0.99,定量限为0.5~5.0mg/kg,于1倍定量限、2倍定量限、10倍定量限3个添加水平下进行加标回收试验,20种化合物平均回收率为72.80%~107.75%,相对偏差>10%。该方法操作方便、简单、快捷、清洁、灵敏度高、重复性好。     

在线凝胶渗透色谱-气相色谱-串联质谱法测定食用植物油中11种有机磷阻燃剂

目的 建立在线凝胶渗透色谱–气相色谱-串联质谱法(GPC-GCMS/MS)测定食用植物油中11种有机磷阻燃剂的分析方法。方法 0.5 g 食用油样品用(3：7)丙酮/环己烷溶液稀释定容至5 mL, GPC-GCMS/MS采用多反应监测模式(MRM)测定,外标法定量。结果 11种有机磷阻燃剂在1～50 μg. L_{^{－ 1}}范围内,线性关系良好,相关系数r>0.9970,方法检出限为1.0～3.0 μg. kg_{^{－ 1}},定量限为3.0～9.0 μg. kg_{^{－ 1}}。空白样品中添加3个水平质量浓度,回收率在65.6～129%之间,相对标准偏差RSD为0.2～13.9%。结论 该方法样品前处理简单,仪器自动化程度高,重现性较好,精密度较高,适用于食用植物油中有机磷阻燃剂的检测。     

磺胺二甲嘧啶间接竞争化学发光酶免疫分析法的建立及应用

建立一种更加灵敏的磺胺二甲嘧啶(SM₂)免疫学检测方法。方法 本研究制备抗SM₂单克隆抗体(SM₂-mAb),用于建立SM₂间接竞争化学发光酶免疫分析法(SM₂-CLEIA),并检测主要动物食品中SM₂残留。结果 本研究制备的SM₂-mAb为IgG_2b亚类,亲和常数为0.12×10⁷ L/mol;SM₂-CLEIA曲线在0.1～1 000 μg/L之间呈现良好的线性关系,相关系数r²=0.990 4,半数抑制浓度(IC₅₀)为4.006 μg/L,检测限为0.174 μg/L,添加回收率为94.41%～104.40%,批内和批间变异系数分别为3.07%和8.22%,与磺胺脒等药物无交叉反应,与SM₂-ELISA试剂盒的阴阳性符合率为100%。结论 建立了灵敏、特异、准确、检测范围宽的SM₂-CLEIA检测方法。     

同位素内标-超高效液相色谱-高分辨质谱法测定酒醅中氨基甲酸乙酯

目的：建立同位素内标法结合超高效液相色谱串联高分辨质谱检测酒醅中氨基甲酸乙酯(ethyl carbamate, EC)含量的分析方法。方法：酒醅样品经超纯水超声提取离心过滤后,以0.1%甲酸水溶液-甲醇溶液为流动相梯度洗脱,通过Hypersil GOLD 色谱柱分离目标物,在电喷雾正离子模式下采用一级全扫模式内标法定量分析。结果：同位素内标定量法能有效补偿样品中基质干扰,EC含量在4～300 μg/L浓度范围内线性关系良好(R_²>0.9993),定量限(LOQ)为2.50 μg/L,检出限(LOD)为1.50 μg/L。实际样品加标回收率在85.17%～97.40%范围之间,相对标准偏差(RSD)为1.12 %～4.11 %。结论：该方法线性、准确度和精密度均满足GB/T 27417—2017《化学分析方法确认和验证指南》的要求,适用于酒醅中EC的分析检测。     

液相色谱—串联三重四极杆复合线性离子阱质谱法测定水生蔬菜中45种抗生素

目的:建立超高效液相色谱—三重四极杆复合线性离子阱质谱法同时测定水生蔬菜中多种抗生素类化合物。方法:样品以含0.1%甲酸的乙腈溶液为溶剂,加入N-丙基乙二胺(PSA)、无水Na₂SO₄和C₁₈净化处理,质谱采用分时段多反应检测—信息关联—增强子离子(SMRM-IDA-EPI)扫描模式及谱库检索技术,通过对化合物保留时间、离子对及EPI谱库检索对比,外标法定量。结果:45种抗生素在1.0~100.0 μg/L质量浓度范围内线性关系良好(R²＞0.99),检出限为0.3~1.0 μg/kg,定量限为1.0~3.0 μg/kg,在3个浓度添加水平下,45种抗生素的回收率为60.4%~121.7%,相对标准偏差为0.9%~10.2%。结论:该方法快速简便、定性能力强,适用于水生蔬菜中45种抗生素类化合物的筛查确证和定量检测。     

超高效液相色谱-串联质谱法测定聚氯乙烯食品接触材料中3种柠檬酸酯增塑剂

目的 建立超高效液相色谱-串联质谱法测定聚氯乙烯食品接触材料中3种柠檬酸酯类增塑剂的方法。方法 采用正己烷/二氯甲烷（1∶1，V/V）提取，经硅胶固相萃取柱净化，乙腈/乙酸乙酯（1∶4，V/V）洗脱，进入UPLC-MS/MS分析，以乙腈和超纯水做流动相，经BEH C₁₈色谱柱（2.1 mm×50 mm，1.7 μm）分离，采用ESI源在MRM正离子模式下检测，外标法定量。结果 3种化合物在线性范围内决定系数R²>0.996，方法检出限0.1~0.6 μg/kg，定量限0.3~2.2 μg/kg，回收率为70.3%~103.1%，相对标准偏差为0.9%~9.8%。结论 该方法分析快速、灵敏、准确，适用于塑料材料中柠檬酸酯类增塑剂含量的检测，为新型增塑剂的添加使用监管提供方法。     

前列舒乐胶囊质量标准研究

目的 建立控制前列舒乐胶囊质量的方法.方法 用薄层色谱法定性鉴别制剂中的淫羊藿、黄芪、川牛膝;用高效液相色谱法(HPLC)测定淫羊藿苷含量.结果 定性鉴定了制剂中的淫羊藿苷、黄芪甲苷及川牛膝;HPLC测定本品淫羊藿苷在0.37～7.47 μg范围内线性关系良好,平均回收率98.9%,重现性试验RSD 2.2%.拟限定本品淫羊藿苷含量为每1 g不得少于8.0 mg.结论 以上方法可有效地控制前列舒乐胶囊的质量.     

分散固相萃取—超高效液相色谱—串联质谱法测定液态奶中11种农药残留量

目的：评估液态乳中农药残留量的安全性。方法：建立同时测定11种农药残留的超高效液相色谱—串联质谱法。待测样品经乙腈提取，C₁₈和PSA固相萃取剂净化，经色谱柱Xbridge BEH C₁₈ （100 mm×2.1 mm，1.7 μm）分离，多反应监测模式进行测定，并使用响应曲面法优化前处理参数。结果：前处理的最佳条件为乙腈用量10 mL，C₁₈用量50 mg，PSA用量30 mg。11种农药在1.0~100.0 μg/L的浓度范围内线性关系良好，相关系数（R²）均＞0.999。在10，20，100 μg/kg添加水平内，11种农药的平均回收率为82.7%~102.0%，相对标准偏差为2.89%~8.87%，检出限和定量限分别为2.0~3.0，5.0~10.0 μg/kg。结论：该方法操作简便，分析时间短，回收率高，重现性好，能够准确定性定量分析液态乳中11种农药残留量。     

高效液相色谱法测定奶粉中玉米黄质含量

目的 本文建立了一种使用高效液相色谱快速检测奶粉中玉米黄质含量的方法。方法 奶粉样品用蛋白酶在45℃条件下振荡酶解30 min,正己烷/丙酮(9：1)重复提取2次,旋转蒸发浓缩至近干,正己烷/乙酸乙酯(65：35)复溶后,用Si 60(100 mm×2.1 mm,5 μm)色谱柱经高效液相色谱紫外检测器测定,外标法定量测得。结果 试验结果表明,玉米黄质在14.018 min附近出峰,玉米黄质浓度在0 μg/mL-4.0 μg/mL范围内呈良好线性关系(R_²=0.99982)。空白奶粉样品中添加玉米黄质含量为63.35 μg/100 g,126.7 μg/100 g,316.75 μg/100 g时,加标回收率在95.8%～96.7%之间,相对标准偏差在1.1%-3.9%之间。当取样量为2 g,定容体积为5 mL时,检测限为20 μg/100 g,定量限为50 μg/100 g。结论 该检测方法相对于其他前处理较简单,具有较高准确度、灵敏度、稳定性,可以满足奶粉中玉米黄质含量的检测。     

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.