超高效液相色谱-串联质谱法同时测定小麦中的4种限量真菌毒素

目的建立复合免疫亲和柱净化-超高效液相色谱-串联质谱法同时测定小麦中4种限量真菌毒素的分析方法。方法小麦样品粉碎后,通过80%的乙腈水溶液(V:V)提取后,采用复合免疫亲和柱净化,并利用超高效液相色谱串联质谱的多反应监测模式进行测定分析。色谱柱为ACQUITYUPLCBEHC18柱(100 mm×2.1 mm, 1.7μm),以10 mmol/L乙酸铵(含0.1%甲酸)-甲醇为流动相梯度洗脱,在电喷雾电离模式下正、负离子同时扫描检测,采用外标法定量。结果在8.0 min内可以完成4种真菌毒素的测定,在相应的线性范围内,回归方程的相关系数均超过0.999,3个加标水平下,回收率为82.0%~103.0%,相对标准偏差为5.2%~9.7%。结论该方法快速、准确、高效,适用于小麦及其制品中4种限量真菌毒素的同时测定。     

超高效液相色谱串联-质谱法同时测定香辛料中7种真菌毒素

建立了同时测定香辛料中7种真菌毒素的超高效液相色谱-串联质谱分析方法(UPLC-MS/MS)。选用香辛料中的辣椒、花椒和八角为研究对象,粉碎后的样品用70%甲醇水溶液提取,6合1免疫亲和柱净化,ACQUITY UPLC HSS T3色谱柱分离,超高效液相色谱-串联质谱测定,电喷雾正离子(ESI+)多反应离子监测方式监测,外标法定量。结果表明,7种真菌毒素在各自的线性响应范围内线性关系良好,相关系数均不低于0.995,7种真菌毒素的定量限为0.5~20 μg/kg。低、中、高3个加标水平平均回收率(n=6)为67.25%~113.47%,相对标准偏差(RSD)为1.07%~10.20%。该方法具有前处理简单、净化效果好、灵敏度高和高通量检测的优点,适用于香辛料中多组分真菌毒素残留的分离和检测。     

UPLC-MS/MS同时测定特殊医学用途配方食品中8种真菌毒素

建立了超高效液相色谱-串联质谱法(UPLC-MS/MS)同时检测特殊医学用途配方食品中黄曲霉毒素、杂色曲霉素和赭曲霉毒素等8种真菌毒素的方法。样品用乙腈-水(80∶20,体积比)溶液提取,经Captiva EMR-Lipid萃取管净化,采用Poroshell 120 SBC18 (2.1 mm×100 mm,1.7μm)色谱柱分离,超高效液相色谱-串联质谱仪进行检测,基质匹配外标法定量。8种真菌毒素在各自的线性范围内线性关系良好(r0.99),加标回收率为92.2%～108.9%,相对标准偏差小于15%。该方法简便、高效,可用于特殊医学用途配方食品中多种真菌毒素的同时快速筛查。     

同时检测食品中多种类真菌毒素的研究进展

食品中普遍存在着多种真菌毒素的共同污染,其联合毒性加剧了健康风险,检测单个或者单一种类的真菌毒素已无法满足保障食品安全的要求,快速、高效且同时检测多种类真菌毒素成为必然趋势。本文简述食品中真菌毒素污染的特点,从样品前处理方法和检测技术两方面介绍目前监测食品中多种类真菌毒素的研究进展。液液萃取、固相萃取、免疫亲和柱法以及QuECHERS法等被应用于多种类真菌毒素同时提取、富集和净化,超高效液相色谱和多级别、高分辨率的质谱联用技术在多组分同时检测和非靶标性真菌毒素鉴定中独具优势。本文可为同时检测食品中多种类型的真菌毒素研究及应用提供参考。     

全碳标记稳定同位素内标-超高效液相色谱-串联质谱法测定粮食中16种真菌毒素

考察高效液相色谱-串联质谱-全碳标记的稳定同位素内标法精确测定小麦和玉米中16种真菌毒素方法的适用性。样品经提取稀释、加入内标,高效液相色谱-串联质谱测定。结果表明,16种真菌毒素线性相关系数大于0.997,3个水平的添加回收率为83%~114.3%,相对标准偏差为0.9%~13%,定量限为0.5~200μg/kg,通过检测FAPAS04223质控样品和小麦、玉米样品验证了方法的准确性和适用性,能够快速、批量、准确的测定小麦和玉米中16种真菌毒素,为我国粮食真菌毒素污染监测提供便利。     

杂质吸附固相萃取–液相色谱串联质谱法同时测定粮食中15种真菌毒素

建立了同步检测粮食中15种真菌毒素的杂质吸附固相萃取–超高效液相色谱串联质谱方法。样品经0.1%酸化84%乙腈水溶液提取,杂质吸附柱Prime-HLB净化后,加入稳定同位素内标补偿基质效应干扰,选择Phenomenon Kinetex Bipheny l100A作为分离柱,采用梯度洗脱,超高效液相色谱–串联质谱（UPLC-MS/MS）检测,内标法定量。结果表明,15种真菌毒素的线性相关系数均大于0.996,检出限为0.2~15 μg/kg,定量限为0.8~30 μg/kg;三种基质3个添加水平的回收率为76.9%~116.1%,相对标准偏差（RSD）为1.4%~10%;对玉米基质标准物质进行检测验证,表明8种真菌毒素的检测值均在标示范围内;采用本方法检测了市售粮食135批次,共有97批样品检出真菌毒素,检出率为71%,多毒素同时污染现象较为普遍。方法可用于粮食及其制品中真菌毒素的快速检测。     

液相色谱-串联质谱测定小麦粉中 11种真菌毒素

建立小麦粉中11种真菌毒素的超高效液相色谱-串联质谱检测方法。样品用乙腈-水溶液提取,经多功能净化柱Pribo Fast 100进行净化,采用XTerra MS C18色谱柱进行分离,以20 mmol/L乙酸铵溶液和乙腈梯度洗脱,利用超高效液相色谱-串联质谱进行分析。11种真菌毒素在测定浓度范围内线性关系良好,各组分相关系数R20.998,加标回收率范围72.4%~90.7%,方法精密度范围6.2%~11.8%,测定各组分真菌毒素定量限范围1.2μg/kg~2.0μg/kg。该方法前处理过程简洁、灵敏度高、重现性好,适用于小麦粉中11种真菌毒素的测定。     

免疫亲和净化-超高效液相色谱-串联质谱法测定食品中玉米赤霉烯酮类真菌毒素

建立食品中6种玉米赤霉烯酮类(α-玉米赤霉醇、β-玉米赤霉醇、α-玉米赤霉烯醇、β-玉米赤霉烯醇、玉米赤霉酮、玉米赤霉烯酮)真菌毒素的免疫亲和净化-超高效液相色谱-串联质谱检测的实验方法。样品经80%乙腈溶液提取,通过免疫亲和柱净化富集,用2 mL乙腈洗脱,氮吹至近干,0.5 mL 50%乙腈溶液复溶,采用超高效液相色谱-串联质谱进行测定。在ACQUITY UPLC HSS T3反相柱上分离,梯度洗脱,流动相为乙腈和水,质谱采集模式为电喷雾负离子多反应监测模式。6种目标物的线性范围为0.1~100μg/L,相关系数(R~2)均大于0.992,检出限为0.05μg/kg,定量限为0.2μg/kg,3个不同水平的加标平均回收率为73.0%~119.1%,相对标准偏差不大于10%。该方法具有操作简单、重复性好、灵敏度高、杂质干扰小等特点,可以用于食品中玉米赤霉烯酮类真菌毒素的检测。     

高效液相色谱质谱法快速测定小麦中DON、ZON、T-2的残留方法研究

建立了快速检测小麦中DON、ZON、T-2的高效液相色谱质谱方法,针对小麦样品的特点,采用50%乙腈/水溶液提取,提取液经氯化钠盐析,反相色谱分离,高效液相色谱-串联四级杆质谱检测,多反应监测模式采集,外标法定量。该方法一次提取,同时测定小麦中3种毒素,具有快速、准确的特点。     

超高效液相色谱-串联质谱法同时测定玉米、花生、麦仁中的9种真菌毒素

建立玉米、花生、麦仁中9 种真菌毒素的超高效液相色谱- 串联质谱确证方法。样品用甲醇- 水溶液和磷酸缓冲液(PBS)双重提取后直接过真菌毒素免疫亲和柱净化;氮气吹干后用的乙腈- 水溶液(50:50,V/V)定容,超高效液相色谱- 串联质谱(LC-MS-MS)测定,电喷雾正、负离子(ESI+、ESI －)多反应模式监测。结果表明,样品中真菌毒素在0.1～400μg/kg 范围内时与其峰面积呈良好线性关系,定量限为0.1～20μg/kg,3 个加标水平下平均回收率为59.5%～118.8%,相对标准偏差为2.4%～12.8%,符合痕量分析的要求。     

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.     

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.     

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.     

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.