食品中有机氯农药测定前处理方法的研究进展

主要阐述了食品中有机氯农药残留的毒性作用以及近年来食品有机氯农药测定方法的研究进展,介绍了近年来液-液萃取技术(传统液-液萃取法、液相微萃取技术)、固相萃取技术(固相萃取技术、固相微萃取技术、分子印迹固相萃取、基质固相分散)、快速溶剂提取技术、凝胶渗透色谱技术、微波辅助萃取技术、超声波提取等样品前处理方法的研究进展。     

液-液萃取稳定同位素内标法测定酒中氨基甲酸乙酯

目的建立液-液萃取稳定同位素稀释测定酒中氨基甲酸乙酯含量的方法。方法以氘代同位素D5-氨基甲酸乙酯为内标,用液-液萃取法稳定同位素稀释,气相色谱-质谱选择离子法测定。结果氨基甲酸乙酯的检出限为1.1μg/kg,回收率为90.7%-106.3%,RSD为2.6%。测定市售10种葡萄酒、15种白酒和20种黄酒,氨基甲酸乙酯含量分别为：葡萄酒5.57-20.7μg/kg、白酒5.8-297μg/kg、黄酒79.8-498μg/kg。结论液-液萃取法精密度和准确度高,简便快速,适用于酒中氨基甲酸乙酯的测定。     

气相色谱-质谱测定黄酒中的敌敌畏

目的建立气相色谱-质谱(GC-MS)测定黄酒中敌敌畏的检测方法。方法同时优化了液液萃取和固相萃取2种前处理方法,液液萃取法称取40 g样品加4 ml甲苯萃取,振摇后加5 g NaCl,5 000 r/min离心5 min,有机相进GC-MS选择离子模式检测分析。固相萃取选用C_(18)柱,经5 ml甲醇、5 ml水活化,称取10 g黄酒上样,过柱后用5 ml水淋洗,2 ml乙酸乙酯洗脱,45℃氮气吹至近干,用乙酸乙酯定容至1 ml进GC-MS分析。结果敌敌畏在0.05 mg/L～10.0 mg/L内线性良好,r值0.999 8。液液萃取法平均回收率为89.4%～94.5%,固相萃取法平均回收率为102%～114%,2种前处理方法最低检出限(LOD)接近,分别是0.125μg/kg～0.155μg/kg、0.150μg/kg～0.204μg/kg。固相萃取法与液液萃取法相比操作简单、回收率高、敌敌畏富集效率高,所用试剂更加环保安全。结论固相萃取与GC-MS联用适用于黄酒中敌敌畏的检测分析。     

茶叶中农药残留检测的样品前处理研究进展

样品前处理是建立各种检测方法中耗时最多、最易引起误差的关键环节之一。综述了茶叶中农药残留检测的样品前处理技术,包括索氏提取、震荡提取、超声提取、固相萃取、固相微萃取、微波辅助萃取、搅拌棒吸附萃取、加速溶剂萃取、超临界流体萃取、凝胶渗透色谱和基质固相萃取技术的研究进展。     

顶空固相微萃取技术的应用与展望

<正>由于实际样品中的待测物质含量比较少,在有基质干扰的情况下,不能直接进行检测,必须通过提取、净化和浓缩等全处理过程,才能满足检测要求,因此样品的前处理技术对数据的准确性、重现性起到至关重要的作用,当前样品前处理技术主要有顶空瓶法、液液萃取、吹扫捕集、固相萃取、固相微萃取、液液微萃取和分散液液微萃取等,而固相微萃取(solid-phase microextraction,SPME)技术(是20世     

超高效液相色谱法测定辣椒油中罗丹明B的3种样品前处理方法比较

目的比较辣椒油中罗丹明B含量测定的前处理方法,为超高效液相色谱荧光法测定辣椒油中罗丹明B选择前处理方法提供参考。方法选取已知罗丹明B含量的辣椒油样品,分别采用超声提取法、WAX固相萃取法和GPC净化法对辣椒油中的罗丹明B进行提取净化,利用超高效液相色谱荧光法进行罗丹明B的含量测定,计算相对误差。用空白辣椒油做高、中、低3个浓度的加标实验,计算回收率,通过相对误差及回收率来评价3种前处理方法的优劣。结果HLB固相萃取法所测结果相对误差10%,且回收率80%,其余方法所测结果相对误差均10%且回收率在80%~110%。结论超声提取法、WAX固相萃取法和GPC净化法均可满足辣椒油中罗丹明B的前处理要求,3种方法各有优缺点,实验人员可根据实际情况选用。     

2011年昆明市市售酒中氨基甲酸乙酯的检测与分析

目的建立固相萃取GC-MS法测定酒中氨基甲酸乙酯(EC),并对昆明市市售酒中EC含量进行检测。方法固相柱萃取净化后,5%乙酸乙酯/乙醚洗脱浓缩,GC-MS法对36个市售酒样中氨基甲酸乙酯进行定量分析。结果该方法检出限为2.0μg/kg,回收率83.95%～91.78%,RSD5%。市售酒的EC含量范围为31.31～1 618.19 g/kg;其中,白酒(26件)中EC含量最高的是瓶装糯谷香酒,含量达1618.19 g/kg;含量最低的是瓶装大麦酒,含量31.31 g/kg。结论 36个样品中均检测出EC,制定我国酒类中EC的限量标准很有必要。     

小白菜中有机磷残留量测定前处理方法比较

目的 采用三种前处理方法检测小白菜中有机磷,以此对比不同方法间的提取差异. 方法 采用固相支持液-液萃取、QuEChERS、液-液萃取三种不同的前处理方法对小白菜样品进行前处理,用毛细管气相色谱法脉冲火焰光度检测器对处理后样品中的有机磷类农药残留进行测定,并对不同前处理方法的样品测定结果的回收率、阳性样品测定值进行比较. 结果 三种方法的测定值回收率和阳性样品测定结果经x2检验和t检验,测定值回收率、阳性样品测定结果差异无统计学意义. 结论 QuEChERS法较为方便简单、溶剂消耗量少,值得推广.     

蔬菜中农药残留的样品前处理方法的研究

[目的]建立一种简便易行,适用于检测蔬菜中4大类农药残留的气相色谱分析样品前处理方法。[方法]以甲胺磷、对硫磷作为有机磷农药代表,灭多威为氨基甲酸酯类农药代表,氯菊酯为菊酯类农药代表,采用液-液萃取、索氏提取、国标固相萃取法、本法的固相萃取法4种前处理方法处理样品,按GB/T 5009.145-2003和GB/T 5009.146-2003法测定并对不同的前处理方法的测定结果进行比较。[结果]该方法所检测的农药的最低检出限为0.002～0.05 0;加标回收率为86.3%～104.9%;相对标准偏差为3.92%～11.08%;校正曲线相关系数为0.997 9～0.999 8。[结论]与国标前处理方法比较,它在保证国标方法要求的精密度和准确性的同时,具有检验时间减少、前处理试剂消耗少、空白的背景干扰小等特点。     

食品中苏丹红一号的检测方法研究

目的：应用高效液相色谱和固相萃取技术测定食品中的苏丹红一号。方法：用固相萃取法对样品提取液进行净化处理，利用反相高效液相色谱法分析食品中的苏丹红一号，在C18色谱柱上，95％的甲醇水溶液做流动相，流速为1．00ml／min，柱温为40℃，紫外检测波长为478nm，可以较好地检测食品中的苏丹红一号，阳性样品由液相色谱一多极串联质谱联用仪确证。结果：该方法相对标准偏差在1．00％-2．36％之间，回收率在87．2％-95．0％之间。线性相关系数r〉0．9992。结论：本方法准确可靠，可应用于食品中苏丹红一号的测定。     

2010年杭州市售发酵性食品中氨基甲酸乙酯调查与分析

目的 调查2010年杭州市售发酵性食品中氨基甲酸乙酯含量.方法 2010年在杭州大、中、小型3家超市采集237份发酵性食品,包括黄酒、白酒、葡萄酒、啤酒、料酒、酱油、食醋、腐乳等8类食品,采用D5-氨基甲酸乙酯核素稀释技术,硅藻土固相萃取净化样品,然后用气相色谱-质谱法测定样品中氨基甲酸乙酯.结果 237份发酵性食品中氨基甲酸乙酯检出率为100%,含量范围为2.0 ~515.0 μg/kg,氨基甲酸乙酯含量平均值(中位数)从高到低依次为红腐乳[182.2 μg/kg(161.2 μg/kg )]、黄酒[159.6 μg/kg(121.0 μg/kg)]、料酒[86.8 μg/kg(95.6 μg/kg)]、白酒[72.0 μg/kg(60.5 μg/kg )]、酱油[47.2 μg/kg(40.7 μg/kg)]、食醋[26.7 μg/kg(31.8 μg/kg )]、葡萄酒[15.7 μg/kg(16.8 μg/kg )]、啤酒[2.2 μg/kg(2.3 μg/kg)].结论 2010年杭州市发酵性食品中均存在氨基甲酸乙酯,尤以红腐乳、黄酒中氨基甲酸乙酯含量为高.

Abstract：

Objective To observe the ethyl carbamate concentrations in different commercial fermented foods in Hangzhou in 2010.Methods In 2010,237 commercial fermented food samples of eight categories,including yellow wine,white spirit,wine,beer,cooking wine,sauce,vinegar and fermented bean curd,were purchased from 3 different size markets respectively in Hangzhou.The ethyl carbamate was measured by gas chromatography-mass spectrometry in selection ion mode,after the samples were coupled with D5-ethyl carbamate,and purified by diatomite solid phase extraction column.Results The results showed that ethyl carbamate was detected in all samples analyzed (100%) with the range from 2.0 μg/kg to 515.0 μg/kg.The ethyl carbamate average(median)levels in 8 food catergories were descending with fermented red bean curd (182.2 μg/kg (161.2 μg/kg)),yellow wine (159.6 μg/kg (121.0 μg/kg)),cooking wine (86.8 μg/kg (95.6 μg/kg)),white spirit (72.0 μg/kg (60.5 μg/kg)),soy sauce (47.2 μg/kg(40.7μg/kg)),vinegar (26.7 μg/kg (31.8 μg/kg)),wine (15.7 μg/kg (16.8 μg/kg)) and beer (2.2 μg/kg (2.3 μg/kg)).Conclusion The ethyl carbamate was detected in all fermented foods in Hangzhou in 2010,and the levels of ethyl carbamate in red bean curd and yellow wine were higher than others.     

The effect of ethanol and alcoholic beverages on gastric emptying of solid meals in humans

AIMS: The systematic study of the effect of pure ethanol, alcoholic beverages, and their non-alcoholic components on gastric emptying of solid meals in humans. METHODS: 16 fasting healthy male subjects received once weekly 300 ml of the following solutions in random order: 4 and 10% (v/v) ethanol, beer, red wine, 5.5 and 11.4% (w/v) glucose, and water. The test solutions were given either together with a low caloric (270 kcal, n = 8) or a high caloric (740 kcal, n = 8) solid meal. Ultrasonography of the antrum was used to determine gastric emptying. RESULTS: Gastric half emptying time (t(1/2) ) of the high caloric solid meal with water was 131.3 +/- 7 min. The ingestion of 4 and 10% (v/v) ethanol (158.8 +/- 9.3 and 165.6 +/- 6.2 min, respectively), beer (163.1 +/- 11 min), and red wine (186.3 +/- 8.4 min) resulted in a significantly longer t(1/2) than water. The lag phases after 4 and 10% (v/v) ethanol, beer, and red wine were not significantly different from that of water (48.1 +/- 6.5 min). Compared with water, the ingestion of 5.5 and 11.4% (w/v) glucose resulted in a significantly longer t(1/2) (153.8 +/- 5 and 168.1 +/- 14.4 min, respectively) by increasing the duration of the lag phase. The high caloric meals resulted in a 2-fold prolongation of t(1/2) when compared with the low caloric meals. The effect of the solutions on the gastric emptying times, however, was similar for both test meals. CONCLUSIONS: (i) Ethanol in low concentrations of 4 and 10% (v/v) prolongs gastric emptying of solid meals; this inhibitory effect is not dose-dependent. (ii) Alcoholic beverages (beer and red wine) also result in a prolongation of gastric emptying. The inhibitory effect of red wine, but not of beer, is more pronounced than that of the corresponding ethanol concentration and amount. (iii) The inhibitory effect of ethanol and alcoholic beverages is mainly induced by a prolongation of the gastric emptying phase (without affecting the lag phase), whereas 5.5 and 11.4% (w/v) glucose prolong the lag phase in a dose-dependent manner. (iv) The inhibitory effect of ethanol, beer, and red wine on gastric emptying does not depend on the caloric content of the meal.     

烟台市发酵性调料中氨基甲酸乙酯污染状况调查

目的:探讨烟台市发酵调料中氨基甲酸乙酯(ethyl carbamate,EC)污染状况,对本地区发酵性调料的食品安全性进行调查与评估。方法:随机选取2011年烟台市超市及食品供销部的158份发酵食品,应用基质固相分散萃取(MSPD)技术GC/MS定量分析各类发酵调料食品中EC的含量。结果:(1)158份发酵性调料食品中阳性样品数为117份,阳性率为74.05%,其中黄酒及料酒中EC阳性率最高,平均含量分别为73.1μg/kg、66.4μg/kg,酱油和食醋中EC的含量相对较低,平均含量为40.3μg/kg、29.1μg/kg,腐乳EC平均含量为27.5μg/kg;(2)EC阳性腐乳样品数为36份,其中红腐乳19份,白腐乳17份,两组间EC含量水平无显著差异性。结论:烟台市发酵调料食品中普遍存在EC,其中黄酒及料酒中EC阳性率最高,且EC含量最高值为100.2 mg/L,发酵调料的食品安全问题应进一步加强监管、严格调控。     

Determination of urinary metabolites of alkyl cellosolves by solid phase extraction and GC/FID

Alkyl cellosolves include ethylene glycol monomethylether, ethylene glycol monoethylether, ethylene glycol monobuthylether. And their urine metabolites are methoxyacetic acid, ethoxyacetic acid and butoxyacetic acid. The current analytical method for urinary alkoxyacetic acid is liquid-liquid phase extraction. But the liquid-liquid phase extraction method needs a more complex pre-treatment process and has a low recovery rate. We determined the appropriate extraction solvent and its flow rate. We also evaluated the non-absorptive rate and recovery rate according to particle size. Finally we developed a convenient solid phase extraction method for the analysis of urine cellosolve metabolites. As a result, the recovery rates for methoxyacetic acid, ethoxyacetic acid and butoxyacetic acid were 100.4 +/- 1.6%, 100.2 +/- 1.8% and 100.7 +/- 10.0% respectively, when acetone was used as the extraction solution. The most appropriate flow rate was 0.1 ml/min. At a particle size of 140-200 mesh, non-absorption percentages for methoxyacetic acid, ethoxyacetic acid, butoxyacetic acid were 3.2 +/- 0.3%, 1.0 +/- 0.1% and 1.1 +/- 0.1%, and the recovery rates according to particle size were similar. Further evaluation of the recovery rate and non-absorptive rate according to the mini column shape, stationary phase and recovery rate with various extracting solutions is required.     

Alcohol, red wine and cardiovascular disease

The objective of this article is to review the existing literature concerning the effects and mechanisms of action of red wine consumption vs. other alcoholic beverages on the risk of cardiovascular disease (CVD). Of particular interest is the form and quantity of alcohol consumed. This relationship between alcohol consumption and mortality is well supported by epidemiologic studies, which have suggested that different forms of alcohol alter the relative risk values for mortality from CVD. Although not without exception, current evidence from epidemiologic and experimental studies suggests a protective effect against the development of CVD with moderate consumption of red wine. The exact nature of the protective effect remains to be established. However, mechanisms including LDL oxidation and alterations in hemostatic variables are being increasingly recognized as contributory. Key components of red wine thought to be responsible for the protective effects include phenolic compounds and alcohol content. Despite the research presented, some questions relating to the current recommendations regarding moderate alcohol consumption and cardiovascular health remain. However, collectively, the literature aids in understanding some of the ways in which alcoholic beverages and their components affect the health of our population.     

Carcinogenicity of dark liquor

To investigate whether the non-alcohol content of distilled alcoholic beverages affects the carcinogenicity of the beverage, we conducted an epidemiologic study of laryngeal and hypopharyngeal cancer. We interviewed 384 cases (or spouses, for deceased cases), and compared their responses with those of 876 controls. We classed distilled liquors as dark or light, a rough division according to content of potentially carcinogenic compounds in the beverages. The relative effect on hypopharyngeal cancer risk was much stronger for those who reported high consumption of dark liquor (relative risk = 4.4, 90% confidence interval = 2.9, 6.8) than for those reporting comparable consumption of light liquor (relative risk = 1.3, 90% CI = 0.8, 2.1). For laryngeal cancer, consumption of dark liquor had a smaller effect, and there was little distinction between the effects of dark and light liquor. The data appear consistent with the theory that the non-alcoholic content of distilled alcoholic beverages is a determinant of cancer risk, and that alcoholic beverages act topically rather than systemically in their carcinogenic action.     

High-density-lipoprotein cholesterol and types of alcoholic beverages consumed among men and women.

OBJECTIVES. Differences by sex in the relationship between high-density-lipoprotein (HDL) cholesterol and consumption of alcoholic beverages were examined in 1516 individuals. METHODS. Questionnaires and blood-sample data from cross-sectional surveys were analyzed. RESULTS. Both beer and liquor were independently associated with increased HDL cholesterol in the total group, in men, and in women after covariates were controlled for. Wine was associated with a significant increase in HDL cholesterol in women only. CONCLUSIONS. Among women and men, amount may be more important than type of alcoholic beverage consumed. The independent effect of wine on HDL cholesterol among men remains unclear since few men in this population consumed wine exclusively or in large quantities.     

Trends in food intake: The 1987 and 1992 national health interview surveys

To examine food intake trends in the US population, cross‐sectional nationally representative food intake data were obtained from the 1987 and 1992 National Health Interview Survey Cancer Control Supplements. In each of these years, approximately 10,000 respondents completed methodologically consistent food frequency questionnaires containing the same 57 food items. Between 1987 and 1992, the proportion of Americans consuming high‐fat foods, including fried fish, fried chicken, bacon, eggs, whole milk, and butter, decreased. The proportion of Americans drinking alcoholic beverages also decreased: fewer drank wine and hard liquor in 1992. The proportion of fruit and vegetable consumers remained stable over time. These results are similar to those obtained from more detailed national surveys. National guidelines urge Americans to avoid intake of high‐fat foods, increase consumption of fruits and vegetables, and practice moderation when drinking alcoholic beverages to prevent cancer and other chronic diseases. The direction of Americans’ apparent changes in food usage between 1987 and 1992, evaluated using limited data from food frequency questionnaires, suggests greater behavioral changes in the direction of guidelines recommending avoidance of foods that may increase the risk of cancer than in the direction of guidelines recommending increased consumption of foods that may confer protection.