固相萃取-流动注射化学发光法测定动物肝脏中的盐酸二氟沙星

碱性条件下,基于盐酸二氟沙星对鲁米诺-过氧化氢化学发光反应体系的抑制作用,样品经固相萃取柱处理后用该体系测定,建立快速分析猪肝、鸡肝中盐酸二氟沙星的流动注射化学发光新方法。结果表明:盐酸二氟沙星质量浓度在1.00×10-5～1.00×10-9mg/mL范围内,质量浓度的负对数与体系的相对化学发光强度呈良好线性关系,方法检出限为4.07×10-9mg/mL,相对标准偏差(RSD)为0.93%(n=11)。该方法用于动物肝脏中盐酸二氟沙星残留的检测,结果令人满意。     

流动注射-化学发光测定香草醛

在酸性条件下,香草醛对Ru(phen)32+-Ce(Ⅳ)反应体系化学发光有显著的减弱作用,据此建立了流动注射-化学发光检测香草醛的新体系。对影响流动注射化学发光的各因素进行了实验研究,优化了反应条件和各项测定参数。结果表明,优化条件下,在质量浓度为4.00×10-7～8.25×10-6g/mL的范围内,相对发光强度与其质量浓度呈对数线性关系,检出限(3σ)为2.90×10-7g/mL,对质量浓度为3.0×10-6g/mL的香草醛进行11次平行测定,相对标准偏差(RSD)为2.6%。对合成样品中香草醛测定的回收率在98.3%～102.8%之间。采样频率120次/h。     

流动注射化学发光法测定饮料中乙基麦芽酚

建立流动注射化学发光测定乙基麦芽酚的新方法。该发光体系中,乙基麦芽酚浓度在3×10-7g/mL～3×10-5g/mL之间时,与相对化学发光强度呈现良好线性关系,方法的检出限为1.1×10-7 g/mL,对5.0×10-6g/mL乙基麦芽酚进行11次平行测定,其相对标准偏差为1.03%。可应用于饮料中乙基麦芽酚的测定,回收率在94%~108%之间。     

流动注射化学发光法测定香草醛

建立流动注射化学发光测定香草醛的新方法.该发光体系中,香草醛浓度在1×10-5g/mL～9×10-4/mL之间时,与相对化学发光强度减小值呈现良好线性关系,方法的检出限为3.6×10-6g/mL,对5.0×10-5g/mL香草醛进行11次平行测定,其相对标准偏差为3.0%.本方法已应用于片剂中香草醛的测定,回收率在98%-102.3%之间,结果令人满意.     

固相萃取-流动注射化学发光法测定奶粉中的三聚氰胺

建立一种快速测定奶粉中三聚氰胺的新方法,利用鲁米诺-高锰酸钾化学发光体系,结合流动注射技术,对样品中的微量三聚氰胺进行测定。结果表明：三聚氰胺对鲁米诺-高锰酸钾化学发光体系具有显著的抑制作用,在最佳实验条件下,方法的线性范围为1×10-11～1×10-6mol/L,检出限(3RSN)为4.0×10-8mg/L,RSD为1.1%(n=11),样品加标回收率为96.1%～102.2%,用于奶粉中三聚氰胺含量的测定,结果令人满意。     

高效液相色谱-Ru（bipy）32+-Ce（SO4）2化学发光体系检测啤酒中的亚硫酸钠

在酸性条件下,Ce(SO4)2氧化Ru(bipy)32+时,在Na2SO3存在下,对该化学发光具有很强的增敏作用,据此建立通过HPLC分离、用化学发光检测器测定亚硫酸钠的方法。在优化的实验条件下,测定亚硫酸钠的线性范围为2.0×10-6～5.0×10-4g/mL,方法的检出限为6.0×10-7g/mL,定量下限为2.0×10-6g/mL,线性回归方程:△I=3.578c+19.721(c:g/mL;r2=0.9984),对5.0×10-5g/mL亚硫酸钠进行了11次平行测定,其相对标准偏差为3.7%。该法已成功的运用于实际啤酒样中亚硫酸钠的含量。     

高锰酸钾化学发光体系检测过氧化苯甲酰

采用高锰酸钾-鲁米诺化学发光体系测定食品添加剂过氧化苯甲酰,研究发现加入过氧化苯甲酰能增强该体系的化学发光.过氧化苯甲酰浓度在0～10×10-5g/mL范围内与发光强度呈良好的线性关系,线性相关系数为0.9993,检出限为8×10-9g/mL.对浓度为3×10-5g/mL的过氧化苯甲酰平行测定20次,相对标准偏差(RSD)为1.32%.     

流动注射抑制化学发光法测定食品中的铝

基于铝(Ⅲ)对鲁米诺-过氧化氢-Cr(Ⅲ)化学发光的抑制作用,建立了一种用于食品中铝含量测定的流动注射抑制化学发光法。化学发光信号降低的程度与铝的浓度在1.0×10-4～2.0×10-3mg/mL和2.0×10-3～1.0×10-2mg/mL范围内线性相关。对流速、样品环长度、Cr(Ⅲ)的浓度、Al(Ⅲ)溶液的酸度、鲁米诺和过氧化氢的浓度等实验参数进行了优化。方法的检出限为2.29×10-5mg/mL。利用所建立的新方法对大米、绿豆、小米等样品进行了测定,回收率为101%～104%,所得结果与ICP-MS方法的结果没有显著性差异。     

反相高效液相色谱 -增敏化学发光测定VB6

基于维生素B6对于鲁米诺(Luminol)和高碘酸钾(KIO4)化学发光反应的增敏作用原理,建立了反相高效液相色谱(RP-HPLC)分离柱后化学发光检测VB6的新方法,并成功运用于饮料中VB6的测定。其中在鲁米诺中加入KBr可以大大增敏该反应。该方法测定VB6的线性范围为5.0×10-7～5.0×10-4g/mL,检测限为2.0×10-8g/mL。对1.0×10-5g/mL的VB6进行连续5次测定的相对标准偏差分别为2.8%,回归方程为Y=954.472X 1.488。     

分子印迹固相萃取-化学发光法测定蔬菜中的马来酰肼

马来酰肼对高良姜素-高锰酸钾-多聚磷酸体系的化学发光具有增敏作用,据此结合分子印迹固相萃取技术建立测定蔬菜中马来酰肼含量的流动注射-化学发光分析方法。以马来酰肼为模板分子,甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,偶氮二异丁腈为引发剂,用热聚合法合成了马来酰肼分子印迹聚合物,并以此分子印迹聚合物作为固相萃取填料制成固相萃取柱,对样品进行固相萃取后进行发光检测。在最优条件下,相对化学发光强度与马来酰肼的质量浓度在5.0×10-5～3.0×10-2mg/mL范围内呈良好的线性关系,检出限2.6×10-5mg/mL(3σ),相对标准偏差2.7%(1.0×10-3mg/mL马来酰肼,n=10)。将该法应用于马铃薯、洋葱及大蒜中马来酰肼含量的测定,加标回收率在95.2%～111.7%之间,相对标准偏差分别为1.8%、2.4%和2.1%。     

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.     

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.     

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.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

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.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the