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1.
建立GC–ECD气相色谱法检测粮食中丁草胺农药残留快速分析方法,粮食样品丁草胺农药残留组分经丙酮+正己烷混合溶剂萃取、石墨碳黑―氨基串联萃取柱小柱净化、GC–ECD程序升温进行分析测定,使前处理步骤简化,方法加标回收率为86%~104%,RSD为1.3%~4.8%。该法简单、快速、基质干扰少,完全可达到对粮食中丁草胺残留量快速分析检测要求。  相似文献   

2.
对粮食样品半消解条件、悬浮液选择、石墨炉程序升温条件、基体干扰等进行研究,建立了半消解悬浮液进样–石墨炉原子吸收光谱法测定粮食样品中镉、铅与砷含量的方法。结果表明,采用标准加入法,将粮食样品进行低温半消解,加入悬浮溶液(0.2%硝酸+0.1%Triton X–100),石墨炉程序升温增加了450℃步骤在空气条件下去除样品基体,得到了良好分析结果,镉、铅以及砷的相对标准偏差(RSD)均小于5%,镉、铅以及砷样品检出限分别为0.20、10.4、11.0μg/L。采用该法测定国家大米标准物质的镉、铅以及砷含量与标准物质证书的结果吻合。因此该法适用于粮食样品中镉、铅与砷的快速测定。  相似文献   

3.
目的 建立电感耦合等离子体发射光谱法(inductively coupled plasma optical emission spectrometer, ICP-OES)测定土壤中镉含量的方法。方法 将土壤样品在微波消解仪中用混酸体系中完全消化, 选用二壬基萘磺酸-煤油体系(dinonylnaphthalenesulfonic acid-kerosene, DNNSA-kerosene)作为浓缩样液中镉的萃取剂, 上机测定。结果 萃取剂体积与消解后定容体积之比为1:10时检测效果最好, 标准曲线的线性范围为0.005~0.100 mg/kg, 线性相关系数为0.9999, 检出限为0.01 mg/kg, 在0.05、0.2、0.5 μg 3个加标水平下, 平均加标回收率为96.8%~104.9%, 相对标准偏差(relative standard deviation, RSD)为0.9%~3.0%。结论 本方法操作简单、实验结果准确可靠, 适用于土壤中镉的测定。  相似文献   

4.
目的 建立一种微波消解-电感耦合等离子质谱法(inductively coupled plasma-mass spectrometry, ICP-MS)测定食用菌基质中有害重金属砷(As)、汞(Hg)、铅(Pb)和镉(Cd)含量的方法。方法 采用硝酸和过氧化氢对食用菌基质样品进行微波消解, 消解液经稀释后用电感耦合等离子体质谱仪测定, 在线内标法定量, 采用国家标准物质土壤(GBW07427)和杨树叶(GBW07604)以及重复性试验, 并经过3个水平的加标回收试验进行验证。结果 测定的不同品种食用菌基质中的4种重金属元素的加标回收率在90.7%~105.3%之间, 相对标准偏差在0.88%~4.03%之间。结论 该方法稳定性好、灵敏度高、定量准确, 提高了检测效率, 适用于食用菌基质中As、Hg、Pb和Cd, 4种重金属快速、准确的定量分析。  相似文献   

5.
《广西轻工业》2016,(8):9-10
原子荧光法是测定硒的常规检测方法。建立以硝酸和过氧化氢为消解体系对大米样品进行微波消解处理,用原子荧光法测定大米中硒含量的方法。硒在0.00μg/L~20.00μg/L范围内线性关系良好,方法的检出限为0.006μg/g,加标回收率在92.0%~104.0%间,标准样品平行测定的相对标准偏差小于2%。该方法具有操作简便快速、灵敏度高、准确度好和用酸量少等优点,适用于大米样品中硒的测定。  相似文献   

6.
采用微波消解法处理大米样品、石墨炉原子吸收光谱法测定大米中镉的含量。此方法的线性范围为0~100.0 ng/mL(R=0.9993),加标回收率为97.78%~100.29%,RSD为0.35%~3.37%(n=6)。该方法取样量少、准确度和精密度高,可作为检测大米中镉含量的方法,为食品安全提供可靠的测定技术保障。  相似文献   

7.
目的建立碰撞池—电感耦合等离子体质谱法(ICP-MS)测定复杂基质化妆品中铬、镍、砷、镉、汞、铅等重金属含量的快速检测方法。方法样品经过微波消解处理,用ICP-MS进行分析,八级杆碰撞反应池结合屏蔽炬技术消除质谱干扰,在线加入内标元素72Ge、115In和209Bi校正基体干扰。结果各元素校正曲线的相关系数均大于0.9992,方法检出限为0.4~2.2 ng/g,相对标准偏差小于5.69%,加标回收率为85.8%~104.2%,有证标准参考物质的测定结果与标准值相符。结论该方法前处理步骤简便快速,适用于复杂基质化妆品中多种有害元素的快速准确测定。  相似文献   

8.
建立石墨消解在电感耦合等离子体质谱测定粮食中重金属的方法。样品经石墨快速消解处理后,用电感耦合等离子体质谱仪进行测定。标准曲线线性范围内线性良好,相关系数R~2均大于0.999,对大米粉样品进行不同浓度加标回收,回收率在90.0%~103.5%之间。方法操作简单、快速、准确。  相似文献   

9.
微波消解-离子选择性电极法快速检测水产品中镉的研究   总被引:1,自引:0,他引:1  
以微波消解对样品做前处理,采用多功能水质仪连接镉离子选择性电极测定水产品中镉含量.实验对溶液DH值、总离子强度调节缓冲液用量的选择、电极的性能进行分析探讨,并对鸢乌贼内脏中镉含量进行实样检测.结果表明,方法的加标回收率为94.3%~113.9%,RSD为0.9%~1.3%,准确度与精密度较好,完全适用于水产品中镉的快速检测.  相似文献   

10.
建立辣椒酱样品中8 种有机氯农药多残留的基质固相分散法-凝胶渗透色谱净化-气相色谱-电子捕获检测器 分析方法。辣椒酱样品首先经基质固相分散法除去大部分油脂和色素等大分子干扰基质后,再通过凝胶渗透色谱进 一步净化,应用气相色谱-电子捕获检测器进行检测。结果表明:测定辣椒酱中8 种有机氯农药的标准曲线相关系数 为0.999 1~0.999 6,加标回收率均在74.58%~102.86%之间,日内相对标准偏差均小于5.45%(n=5),方法检出限 为0. 40~1.20 μg/kg。该方法具有检出限低、灵敏度高、快速、准确的特点,可适用于辣椒食品中多种有机氯农药 残留同时检测。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
16.
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.  相似文献   

17.
18.
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.  相似文献   

19.
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.  相似文献   

20.
<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  相似文献   

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