反相高效液相色谱法直接测定葡萄酒中非挥发酸

葡萄酒中有机酸,一部分来源于葡萄汁,另一部分则是葡萄汁发酵过程中的副产物。葡萄酒中有机酸的含量是葡萄酒质量检验的重要指标之一,它对口感起决定性作用,是决定葡萄酒风味的重要因素。对葡萄酒中有机酸的分析测试方法较多,例如酸碱滴定、比色分析、荧光分析、酶法测定、衍生化色谱分离等。近年来Blanco、Marce用双柱串联的方法,直接进样分析了葡萄酒中的有机酸。 本文介绍用ODS色谱柱直接进样测定葡萄酒中七种有机酸,讨论了影响测定的各方面因素。本法具有速度快、操作简便、样品不经处理等特点,足以满足葡萄酒中有机酸的测定要求。     

衍生化反相高效液相色谱测定葡萄酒中有机酸的研究

葡萄酒中有近百种有机酸,其中主要是乳酸、乙酸、酒石酸、苹果酸、柠檬酸和琥珀酸,它们的含量占葡萄酒中有机酸总量的95％以上。这些酸的含量决定着葡萄酒的口感、品质和稳定性等特性。葡萄酒中有机酸的主要测定方法有酸碱滴定法、纸色谱法、薄层色谱法“和气相色谱法等。近年来,离子色谱法和直接高效液相色谱法得到重视,但由于检测方法的限制和葡萄酒中其它物质的干扰,使这两种方法的检测灵敏度及定量结果受到影响。     

界面衍生化气相色谱法测定葡萄酒中总有机酸

利用离子交换树脂分离、富集葡萄酒中总有机酸并直接在树脂界面上乙酯化,结合气相色谱／质谱法,鉴定并分析了葡萄酒中２１种有机酸。     

天然酚、有机酸的高效液相色谱分析的进展

对近十年来高效液相色谱法在茶叶、葡萄酒、果汁、药物、化妆品等物质中天然酚、有机酸类化合物分析中的应用研究进行了详细评述(引用文献39篇)。     

葡萄酒中酚类的高效液相色谱分析

１前言葡萄汁发酵过程中可能产生极微量的酚，微量酚作为葡萄酒风味成份，但酚类过高就成为有害物质，葡萄酒中酚类的控制是提高酒质量的重要一环。葡萄酒制作过程中使用发酵罐，储存和运输过程中使用塑料桶。环氧树脂常用来作为塑料树脂的添加剂，环氧树脂也广泛使用在罐、管道内部密封、补漏、修复。环氧树脂单体成份：双酚Ａ、双酚Ｆ．其分解产物：苯酚、甲酚、４－叔丁酚等容易进入盛装的葡萄酒中，对葡萄酒产生污染，酒中过高的酚类有毒性和异味，会造成人类健康的损害，与酒类接触的环氧树脂必须严格限制。我国国家标准对葡萄酒中酚类…     

流动注射在线预浓集－火焰原子吸收光谱法测定葡萄酒中微量铅

流动注射在线预浓集－火焰原子吸收光谱法测定葡萄酒中微量铅孙晓娟（江苏石油化工学院应用化学系，常州，２１３０１６）Ｂ．ＷｅｌｚＭ．Ｓｐｅｒｌｉｎｇ（Ｐ－Ｅ有限公司，Ｄ－８８６６２　于伯林根，德国）关键词铅，葡萄酒，微波消解，流动注射在线预浓集，火焰原子...     

多步斜坡升温——恒温平台石墨炉法直接测定葡萄酒中微量铅

研究了一种直接测定葡萄酒中微量铅的方法，以硝酸－磷酸二氢铵体系为基体改进剂，采用多步斜坡并温，恒温平台石墨炉技术，测定了四个国家五种类别葡萄酒中微量铅，回收率９７％～１０４％，精密度优于３．９％。     

测定啤酒和白葡萄酒中有机酸的离子排斥色谱法

研究了离子排斥色谱法分离测定啤酒和白葡萄酒中有机酸；选用常见的盐酸溶液作淋洗液，以四丁基氢氧化铵为再生液，考察了淋洗液浓度、流量等因素对分离和测定的影响，对啤酒和白葡萄酒中常见有机酸在阴离子排斥色谱柱上的保留行为进行了系统的研究；通过试验确定最佳的色谱条件为盐酸浓度1．10mmol/L，流量0．80mL/min；四丁基氢氧化铵浓度5.0mmol/L，流量1.10mL/min；并在该条件下，测定了啤酒和白葡萄酒中的有机酸。     

相转移催化酯化反相高效液相色谱法测定食品中有机酸

在不预分离水相中有机酸的情况下，用α－溴苯乙酮作酯化试剂，以１８－冠醚－６作相转移催化剂直接酯化有机酸，酯化液直接用高效液相色谱分析，紫外检测器检测，操作简便、干扰小、变异系数ＣＶ％＝１．４－５．６％检测下限５－２０μｇ／Ｌ，实际样品回收率９０．９－１０３．３％。     

多波长叠加近红外吸收光谱法直接测定酒精饮料中的乙醇

利用乙醇在１３８２ｎｍ，１６９１ｎｍ和１７３０ｎｍ处的吸光度值，采用多波长叠加近红外吸收光谱法测定乙醇的含量。结果表明，乙醇在０％～２４％（Ｖ／Ｖ）浓度范围内呈良好的线性关系；回归方程为： Ａ＝ ０． ０１７５４＋ ０． ０４７４７Ｃ；相关系数ｒ＝０． ９９９４。用该法可直接测定葡萄酒、啤酒和黄酒中乙醇的含量，６次平行测定的ＲＳＤ分别为；葡萄酒４．０％，啤酒２．５％，黄酒２．４％。回收率为９７．５％～１０５．０％，本方法具有操作简便，准确和快速等优点。     

Development of a two-dimensional liquid chromatography system with trapping and sample enrichment capabilities

A solid-phase microextraction (SPME) followed by a gas chromatographic-mass spectrometric (GC-MS) determination has been developed and validated for the determination of cyprodinil and fludioxonil in white wine samples. Extraction parameters such as the selection of SPME coating, the effect of the temperature, the effect of the headspace volume and the salt addition were studied and optimized, together with GC-MS analytical conditions. The divinylbenzene-Carboxen-polydimethylsiloxane (DVB-CAR-PDMS) fiber was the most appropriate for the determination of the two pesticides in wine. The quality parameters of the proposed method demonstrated a good precision (RSD about 5%), with detection limits of 0.1 and 0.2 microg/l for cyprodinil and fludioxonil, respectively. Fifteen commercial white wine samples produced in Rías Baixas area in Galicia (N.W. Spain) were analyzed with the SPME-GC-MS procedure. Some of the commercial wines (75%) presented the two pesticides in concentrations ranging from 0.9 to 28.6 microg/l. In conclusion, SPME-GC-MS has a great potential for fungicide determination in wines.     

Determination of minor and trace volatile compounds in wine by solid-phase extraction and gas chromatography with mass spectrometric detection

A new method for the quantitative determination of important wine odorants has been developed. The wine (50 ml) is extracted in a 200 mg solid-phase extraction (SPE) cartridge filled with Lichrolut-EN resins from Merck. The elution is carried out with 1.3 ml of dichloromethane. These extracts are directly analyzed by GC-Ion Trap-MS without further concentration. Twenty-seven important wine odorants, such as volatile phenols, vanillin derivatives, aliphatic lactones, nor-isoprenoids, minor esters and terpenols, can be quantitatively determined in a single gas chromatography-mass spectrometry (GC-MS) run. The recoveries in the SPE isolation are in good agreement with those expected from the calculation of breakthrough volumes from solid-liquid distribution coefficients and are higher than 90%, except for guaiacol, vanillin, 2,6-dimethoxyphenol and 4-vinylphenol. In most cases, precision is below 10%. Method linearity is satisfactory, with r2 higher than 0.99 in all cases. The analysis of spiked samples has shown that there is good agreement between the real mass of compound added to the wine and that determined by analysis. In all cases detection limits are below the odor detection threshold of the compounds, and the calibrated interval covers the natural range of occurrence of the compounds in wine.     

GC-MS法检测生物检材中的白酒和啤酒

用GC-MS法分析白酒和啤酒中的成分,统计出白酒、啤酒的各自特征成分并加以比较。对添加不同量白酒、啤酒及白酒与啤酒混合物的胃内容物进行检验,对饮用不同量白酒、啤酒及白酒与啤酒混合物的人员分别采集血样进行检验,统计并总结出胃内容物及血液中白酒、啤酒的区分检验方法。当生物检材中乙醇含量大于0．3mg／mL时,利用该方法可以区分检材中的白酒和啤酒。     

Determination of chloroanisole compounds in red wine by headspace solid-phase microextraction and gas chromatography-mass spectrometry

The objectives of this study, were the development and validation of an analytical method for the determination of 2,4,6-trichloroanisole (TCA), 2,3,4,6-tetrachloroanisole (TeCA) and pentachloroanisole (PCA) in red wine by headspace solid-phase microextraction and GC-MS as well as the application of the optimized and validated method for the quatification of chloroanisoles in different red wines from Navarra. To carry out this study, the extraction variables have been optimized. The fiber and the experimental design selected permit the determination of low analyte concentrations (ng/L) with good accuracy (<5%). Moreover, an analytical method for the determination of TCA and TeCA in wine by GC-MS has been validated. The results obtained in the validation step, recovery values, detection and quantitative limits, and precision were acceptable for all the analytes in the ranges of concentration studied (<5% and <10% for TCA and TeCA, respectively). This method has been used as an analytical method for the quantification of TCA and TeCA in red wine samples that were selected for this study, yielding good results.     

Microextraction of volatile compounds from wine samples and their determination by GC-FID. The effect of the salts and extraction solvents used

Summary This study describes the optimization of microextraction as a method for extracting volatile compounds from wine. The study has been applied to twelve compounds present in wine: 3-methylbutyl acetate, 3-methyl-1-butanol, ethyl hexanoate, hexanol, ethyl octanoate, butanoic acid, ethyl decanoate, diethyl succinate, hexanoic acid, phenylethanol, octanoic acid, and decanoic acid. These compounds were selected from those identified by GC-MS analysis of a real wine sample. By means of a synthetic wine, the study investigated the influence on extraction yield of the solvents and salts used, the proportion of salts, and the agitation time. The determination was performed by GC with flame ionization detection and an internal standard was used for quantification. The method was applied to samples of white wine from La Rioja.     

Comparison of the volatile aroma components in noble rotted grape berries from two different locations of the Tokaj wine district in Hungary

The most famous wine type of Hungary is Tokaji Aszú. Noble rotted botrytised (Aszú) grape berries and a specific vinification technology give its unique delicious aroma and taste. The present work compares volatile aroma components of noble rotted Aszú grape berries from two different locations in the Tokaj wine district. Aszú grape berries have been soaked in 10% ethanol-containing water solutions and thereafter extracted with Freon 11. Volatile components were determined by gas chromatography-mass spectrometry (GC-MS). The total ion chromatograms contained 220-260 components. More than 80 components are identified, among them alcohols, aldehydes, acids, acetals, esters, epoxides, nitrils, furan derivatives and lactones. The compositional differences between the two Aszú grape samples are analysed according to the different component classes. The differences are quantitative rather than qualitative. Some δ-lactones are identified for the first time in noble rotted berries from Tokaj. These substances have very characteristic odor notes such as coconut, chocolate, peach, fruity. Together with the identified γ-lactones they seem to be characteristic aroma components of Tokaji Aszú wines.     

Gas chromatographic determination of 29 organic acids in foodstuffs after continuous solid-phase extraction

A simple and expeditious method based on continuous solid-phase extraction and gas chromatography-mass spectrometry (GC-MS) was reported for the direct determination of 29 organic acids in food and beverages. A sorbent column packed with 80 mg of LiChrolut EN-Supelclean ENVI-18 (1:1) was employed for extraction and clean-up purposes. After elution with 200 μL of methanol, the methanolic extract was directly injected into the GC-MS without prior derivatization. The method provided good linearity (0.5-1000 μg kg⁻¹) and fairly good precision for all compounds (RSD lower than 6.2%). The recoveries of the organic acids from diluted samples that were spiked at three different concentrations (10, 40 and 100 μg kg⁻¹) ranged from 93 to 98%. The applicability of the method was demonstrated by analyzing the target compounds in a wide variety of foodstuffs including beer, wine, fruit juice, soy sauce, soya milk and honey samples.     

Evaluation of the analyses of tert-butyldimethylsilyl derivatives of naphthenic acids by gas chromatography-electron impact mass spectrometry

Naphthenic acids are a complex mixture of carboxylic acids with the general formula CnH(2n+Z)O2 and they are natural, toxic components of crude oils. GC-MS analyses of tert-butyldimethylsilyl esters of naphthenic acids are used to estimate component distribution within naphthenic acids mixtures. Our evaluations of the GC-MS method showed that ions from column bleed erroneously appear as C14 Z = -4 acids and that correcting for heavy isotopes of C and Si do not significantly affect ion distribution plots. Overall, the GC-MS method appears to overestimate the relative proportion of low-molecular-mass acids.     

Dispersive liquid-liquid microextraction using non-chlorinated, lighter than water solvents for gas chromatography-mass spectrometry determination of fungicides in wine

A novel and low solvent consumption method for the sensitive determination of fungicide residues in wine samples is proposed. Analytes were extracted by dispersive liquid-liquid microextraction (DLLME) and further determined by gas chromatography-mass spectrometry (GC-MS). Under optimized conditions, a binary mixture of acetone and 1-undecanol (0.5 and 0.05 mL, respectively) was used to extract target compounds from diluted (1:1) wine samples. After centrifugation, the floating phase of 1-undecanol was solidified and separated from the liquid hydro-alcoholic matrix. Thereafter, it was allowed to melt at room temperature and injected in the GC-MS system. The method showed relative standard deviations (RSDs, %) below 13%, limits of quantification (LOQs) between 0.2 and 3.2 ng mL(-1) and linear responses for concentrations up to 300 ng mL(-1). The efficiency of the liquid-phase microextraction process was scarcely affected by the characteristics of wine samples, consequently pseudo-external standard calibration (using matrix matched standards of red and white wine) sufficed to achieve acceptable accuracy values: relative recoveries from 81 to 120%. The applicability of the method was demonstrated with commercial wine samples.