大豆中磺酰脲类除草剂残留量的检测

为检测大豆中除草剂的残留量，建立了RP-HPLC和HPLC-MS选择离子监测（SIR）同时检测大豆中10种磺酰脲类除草剂残留量的方法。试样经乙腈提取，正己烷液-液分配，弗罗里硅土填充柱净化，然后采用RP-HPLC-DAD和HPLC-ESI（＋）-MS测定。对HPLC和LC／MS分离条件、试样前处理条件进行了研究和优化。建立的方法简便、快速、灵敏。10种磺酰脲类除草剂HPLC法测定，在0．1-10．01μ/ml范围内线性相关系数为0．9996—0．9997，在0．05—2．00mg／kg浓度范围之间，加标回收率均在69．8％-100．7％，其多次测定的RSD在1．9％-10．4％之间，最低检出限均为20μg／kg。LC-MS法测定在0．025—1．0μg／ml范围内线性相关系数为0．9995—0．9998，在0．02-0．1mg／kg浓度范围之间，加标回收率均在72．1％-98．8％，其多次测定的RSD在0．9％-7．7％之间，最低检出限均低于10μg／kg。本方法可满足进、出口大豆中多种除草剂残留量同时检验的工作需要。     

雌酮免疫分析方法的研究

对实验室制得的雌酮特异性抗体A—E1和针对雌酮、雌二醇、雌三醇的广普性抗体A一17E2进行了效能指标的系统评价，建立了雌酮测定的直接竞争ELISA方法。其结果两者检测雌酮的灵敏度分别可达1．3μg／L±0．06μg/L和1．5μg／L±0．05μg／L，检出限分别可达0．04μg／L±0．01μg／L和0．07μg／L±0．01μg／L。此外，A-17E2对于雌二醇和雌三醇的检测灵敏度分别可达1．5μg／L和18μg／L，对两者的检出限分别可达0．04μg／L和0．2μg／L，证明此种广普性抗体可有效检测雌酮，同时对雌二醇、雌三醇也有良好的检测效果。     

克伦特罗残留量的检测方法

研究了应用酶免疫反应(ELISA)方法检测肉品中克伦特罗(Clenbuterol)残留量的制样和运用德国R—Biopharm公司克伦特罗残留测定试剂盒测定的具体操作方法及注意事项，可将克伦特罗检测下限达到0．1μg/kg。     

甲胺磷残留检测直接竞争ELISA试剂盒的研制

研制了二种用于检测蔬菜中甲胺磷残留量的直接竞争酶联免疫测定（EusA）试剂盒，结果表明，该试剂盒的最低检测限为0．01μg/mL，线性检测范围为0．01μg／mL～100μg/mL，标准曲线的平均板内变异系数为4.05％，板间平均变异系数为13．66％，回收率的范围在93．12％～102％。试剂盒在4℃下至少可以保存6个月以上。     

毛细管柱气相色谱法测定食品中微量甜蜜素

研究了测定食品中微量甜蜜素的毛细管柱气相色谱ECD分析方法。结果显示，该法的线性范围是0．01～10．0μg／mL，最低检出限为0.05μg／g，回收率为93.0％～104．0％。     

茶叶中优乐得和菊酯类农药的监测与污染评价

采用气相色谱分离，ECD测定茶叶中优乐得、甲氰菊酯、氰戊菊酯的残留量。结果：对3种农药检测的回收率范围为72．0％-100.3％，相对标准偏差为2．5％-5．6％，最小检出限为O．01μg／mL-0．05μg／mL。采用本文的测定方法检测了采自福鼎、永川、蜀永、缙云山和川茶五个茶园的茶叶样品中的优乐得和菊酯类农药含量，结果表明不同茶园的茶叶中优乐得和菊酯类农药的检出量差异很大。同时，对这几种茶叶的农药残留进行了污染评价。     

ICP-MS法测定食盐中痕量铅镉砷铬的研究

采用电感耦合等离子体质谱(ICP—MS)法，对食盐中痕量铅镉砷铬进行了分析。对影响其测量的各种因素进行了较为详细的研究，确定了实验的最佳测定条件。结果表明，方法的检出限为：Pb0，003μg／L，Cd0．005μg／L，As0．003μg／L，Cr0．008μg／L，回收率为93．33％-109．52％，RSD小于3.68％。该法准确、快速、简便，应用于食盐中痕量铅镉砷铬的测定，效果满意。     

广州市场部分蜜饯中SO_2残留量调查

采用国标GB／T5009．34——2003第2种方法（蒸馏法）对广州市场上7类共43个蜜饯产品中的SO2残留量进行分析测定,同时测定样品中的糖度、总酸度和水分含量等指标。结果显示,SO2残留量超过国家GB2760——2007《食品添加剂使用卫生标准》规定标准（0．35g／kg）的有10个产品,占调查总数的23．26％,残留量为0．4704—3．8411g／kg;残留量超标严重的两个波萝果脯产品分别超出规定标准的9．08倍和10．97倍;合格产品的SO2残留量为0．0005～0．2530g／kg。调查结果表明,同类产品不同厂家之间的SO2残留量差异较大。     

分光光度法测定熟食中苯甲酸、山梨酸的研究

本文研究了二阶导数紫外分光光度法测定熟食中苯甲酸、山梨酸的方法，同时对两种酸之间的相互干扰和基体干扰进行了研究。回收率为98％—105％，优于国标GB／T5009．28—1996气相色谱法(60％)，与校正曲线法(95％—105％)相当，最低检出限分别为1．0μg／mL和0．3μg／mL。本法已用于熟食中苯甲酸、山梨酸的测定。     

顶空气相色谱法测定植物油中的溶剂残留量

建立了顶空气相色谱法快速测定植物油中溶剂残留量的方法。采用Rtx-1毛细管柱和氢火焰检测器测定,外标法定量。结果表明在0．00μg-173．00μg范围内,正己烷的峰面积与其含量呈良好的线性关系,相关系数为0．9993,检出限为1．8mg／kg,平均加标回收率为73．12％-105．25％,相对标准偏差为2．9％～5．4％（n=5）。该方法简便快速、结果准确、重现性好,适合植物油中溶剂残留量的测定。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

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.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

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.