Solid-phase extraction and determination of trace aroma and flavour components in cider by GC-MS

Summary Minor volatile compounds are responsible for the aromas of cider. A simple technique for the analysis of these components is described based on solid-liquid phase extraction followed by quantitation by gas chromatography-mass spectrometry (GC-MS). The method is quantitative for analysis of alcohols, esters, lactones, phenols, and medium and long chain-length fatty acid.     

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.     

固相微萃取与气相色谱-质谱法分析烟用香精的香气成分

采用固相微萃取顶空取样技术和气相色谱 质谱法对烟用香精002的香气成分进行了分析鉴定,对总离子流色谱图的峰面积进行归一化定量。在固相微萃取中使用85μm聚丙烯酸酯(PA)和100μm聚二甲基硅氧烷(PDMS)作为萃取纤维,在烟用香精分析中取得了满意的实验结果,为研究其在卷烟中的致香机理、为卷烟配方设计人员和调香技术人员提供技术依据和参考价值。     

蒸馏-萃取法与溶剂萃取法提取杏果实香气成分的比较

采用水蒸气蒸馏一萃取法和溶剂萃取法提取杏果香成分,用气相色谱一质谱联用测定其化学成分和质量分数,并对两种提取方法进行了比较。水蒸气蒸馏一萃取法提取的杏果香成分是74种,占总峰面积的73．604％;溶剂萃取法提取的杏果香成分是32种,占总峰面积的44．677％,两者相同的成分有21种。溶剂萃取法提取的主要是烷烃类化合物,水蒸气蒸馏萃取法提取的主要化合物为G醛类、C6醇类、内酯类、萜烯醇类、酮类、烷烃类等。结果表明：水蒸气蒸馏-萃取法能较好地提取杏果实香气成分。     

Gas chromatographic-mass spectrometric analysis of volatile compounds in oak wood used for ageing of wines and spirits

Summary Characterization of French oak samples used in the ageing of wines and spirits can be achieved by determination of the composition of their volatile fraction. Soxhlet extraction and simultaneous extraction-distillation have been used to obtain different voltatile fractions. analysis of these fractions by gas chromatography-mass spectrometry enables tentative identification of up to ninety six components including phenols, furans, terpenes, acids, esters, and lactones. The results obtained depend on the method and solvent used.     

Rapid identification of volatile compounds in aromatic plants by automatic thermal desorption — GC-MS

Summary Thermal desorption is a valuable method for the fractionation of plant volatile components, which can be carried out on-line with GC analysis. The use of coupled GC-MS affords additional qualitative information, of special interest for plant species whose composition has not been previously studied. Some examples of the application of automatic thermal desorption, coupled to GC-MS to the identification and characterization of volatile components of plants of different families are given.     

Headspace solid-phase micro-extraction gas chromatography-mass detection method for the determination of butyltin compounds in wines

Butyltin compounds are widespread contaminants which have also been found in some wines, determined by liquid-liquid extraction followed by alkylation with a Grignard reagent and gas chromatography-mass spectrometric (GC-MS) analysis. A promising alternative to this extraction/derivatization method is the one-step tetraethylborate in situ ethylation/solid-phase micro-extraction (SPME) method. In this work, a SPME-GC-MS method for the determination of butyltin compounds in wine was optimised. The optimised parameters concerned the pre-treatment with tetramethylammonium hydroxide, matrix modification with sodium chloride, tetraethylborate concentration, extraction time and temperature, and the GC separation program. The analytical figures of merit of the optimised method (range, limit of detection (LOD) and reproducibility) were evaluated. The sensitivity (range 20-1421 kcounts μg⁻¹ l⁻¹ as Sn) and LOD (range, 0.01-0.2 μg l⁻¹ as Sn) depended greatly on the butyltin species to be measured and on the type of wine. For the tested species (monobutyltin, dibutyltin and tributyltin) the highest sensitivities were achieved for Port wine samples, followed by red wine>white wine>white Verde wine. The method allowed acceptable repeatability (relative standard deviation (R.S.D.), 6-8%; n=4) and reproducibility (R.S.D., 8-9%; n=3).     

Comparison of two methods based on dynamic head-space for GC-MS analysis of volatile components of cheeses

Summary Two methods based in dynamic headspace sampling have been compared for GC/MS analysis of volatile components in hard cheeses (Manchego and other ewe’s milk varieties). In the first approach a purge & trap concentrator allowed volatile on-line determination with reduced sample handling. The second method consisted of a manual device for trapping dinamically purged volatiles, which were then anaysed by using an automatic thermal desorption system, coupled on-line with a GC-MS. The influence of the most significant operating parameters (desorption times, flows and temperatures) on recovery and repeatability was studied for both methods. Automatic purge & trap gave the best sensitivity and repeatability for high valatility components, probably because its on-line operation mode, while the second procedure allowed the determination of a greater number of volatile components and gave better yields for fatty acids and other medium volatility components.     

超声雾化顶空单滴微萃取-气相色谱-质谱法测定果汁中的芳香成分

本文建立了超声雾化顶空单滴微萃取-气相色谱-质谱(GC-MS)联用测定果汁中的β-月桂烯、D-柠檬烯和异戊酸叶醇酯含量的方法。考察了萃取溶剂、萃取时间、富集时间等影响芳香成分萃取效率的因素。在最优的实验条件下,对三种果汁中的芳香成分进行了分析,测得三种果汁中β-月桂烯、D-柠檬烯和异戊酸叶醇酯的含量分别为12.0~488.6μg·mL~(-1)、542.8~1.237×10~4μg·mL~(-1)和0.0470~498.5μg·mL~(-1)。方法的回收率范围为78.5%~110.4%,相对标准偏差为1.3%~4.4%。     

Determination of histamine in port wines and grape juices by ion-pair extraction and stable isotope dilution GC-MS

Summary An isotope dilution, GC-MS method for the quantitation of histamine in wines and grape juices was assayed. This method includes isolation of histamine and its, deuterated analogue [α,α,β,β-²H₄]histamine, used as the labelled internal standard, by ion-pair extraction with bis-2-ethylhexylphosphate, conversion to the volatile derivative: tris-pentafluorobenzyl-histamine, capillary GC separation and measurement of the abundance ratio of the (M-181)⁺ ions from labelled and unlabelled derivatives. The method was successfully applied to the determination of histamine in several samples of Port wine, red and white table wine and grape juice. Data are given on detectability, linearity, repeatability and recovery.     

气相色谱-质谱联用法研究蛇油中腥味物质成分

采用真空-挥发-平衡的方法将蛇油挥发组分进行有效的收集,然后利用气相色谱-质谱联用(GC-MS)的手段对蛇油中的异味或腥味物质进行了分离腚和鉴定,并对除异味处理前后的蛇油挥发组分进行了对比.实验结果发现,蛇油中的腥味物质主要是中碳链的饱和与不饱和的低沸点的醛类、烯醛和烯醇类.质谱检索的结果为己醛、庚醛、2-辛烯醇、2-壬烯醇、2-壬烯醛、2-癸烯醛等,此分析方法的建立对蛇油的深度开发利用很有意义.     

固相微萃取结合气-质联用分析麻椒挥发性成分

以四川广元产的麻椒为原料,利用固相微萃取技术对麻椒中的挥发性成分进行提取,分别用装有HP-5ms和HP-INNOWAXms两种色谱柱的GC-MS进行分离与鉴定;采用质谱与保留指数进行定性,共鉴定出99种成分,其中烯烃类58种、醛类15种、醇类9种、酯类7种、酮类3种、其他烃类4种、其他化合物3种。采用面积归一化法确定了它们相对含量,含量较高的有芳樟醇、D-柠檬烯、β-崖柏烯、β-水芹烯、β-月桂烯、β-蒎烯、(-)-右旋吉玛烯、石竹烯、γ-萜品烯、3-崖柏烯、(Z)-β-罗勒烯、(1R)-(+)-α-蒎烯、(+)-3-蒈烯、(Z,Z,Z)-1,5,9,9四甲基-1,4,7环-十一碳三烯、萜品油烯。从鉴定出的挥发性成分的香气特征可知,烯烃类、醇类和醛类对麻椒的香气贡献较大。     

GC-MS法快速测定茶叶中脂肪酸

建立了气相色谱-质谱联用技术(GC-MS)快速分析茶叶脂肪酸的新方法.对23批茶叶样品进行GC-MS分析,结合NIST 05谱库检索鉴定茶叶脂肪酸种类,并用峰面积归一化法测定其相对含量,比较不同加工方式的茶叶脂肪酸含量.结果表明,所有茶样中亚麻酸、亚油酸和棕榈酸含量最高,但绿茶和青茶脂肪酸含量高于发酵处理的红茶和黑茶.方法可以用于分析各种茶叶的脂肪酸,反映不同种类茶叶的性质差异.     

不同种兰花香气成分分析

利用固相微萃取和气相色谱-质谱联用(GC-MS)技术分析了5种兰花的香气成分。结果表明,5种兰花香气成分的种类和含量存在明显差异。绿苹果(Den.LittleGreen Apples)主要由反-2-己烯醛、己醛、丁羟甲苯、乙酸乙酯和3-己烯-1-醇等化合物构成,其中乙酸乙酯和反-2-己烯醛可能是花朵中苹果香的主要来源。香水文心兰(Onc.Sharry Baby)的主要香气化合物是顺-3,7-二甲基-1,3,6-辛三烯、3,7-二甲基-2,6-辛二烯-1-醇和3,7-二甲基-1,6-辛二烯-3-醇,三者的相对含量总和为84.57%。台北小姐(Cym.Miss Taipei)香气成分的主要特征不明显,除4-甲基苯酚和2-乙基丁醛外,其他化合物的相对含量均低于5%。夕阳红(Phal.Taida Salu)有香气成分50种,相对含量为87.01%,主要成分为柯巴烯、正己烷、甲酸己酯和3-己烯-1-醇。绿世界(Blc.Sung Ya Green‘green world’)有香气成分37种,主要由丙基环丙烷、2-(4-甲氧基苯基)乙醇、反-2-己烯-1-醇、3-己烯-1-醇、反-2-己烯醛、丁基呋喃和3,7,11-三甲基-1,6,10-十二碳三烯-3-醇等组成。     

Improved method to quantitatively determine powerful odorant volatile thiols in wine by headspace solid-phase microextraction after derivatization

A solid-phase microextraction (SMPE) method coupled to a gas chromatography–mass spectrometry analysis was optimized to analyze the pentafluorobenzyl bromide (PFBBr) derivatives of the volatile thiols 4-methyl-4-mercapto-2-pentanone (4MMP), 3-mercaptohexyl acetate (3MHA) and 3-mercaptohexanol (3MH) in wine. This method used deuterated analogue compounds as internal standards. It allowed us to significantly reduce the matrix effect, resulted in good repeatability for all the compounds (RDS < 9.5% for 4MMP; <6% for 3MH and <4.1% for 3MHA) with limits of detection below their odour thresholds. The method was validated using white, rosé and red wines. When applied to analyze different wines, quantities closed to the odour threshold were determined.     

Statistical evalution of aroma and metal content in Tokay wines

Wine qualities are predominantly determined by the qualitative and quantitative composition of organic and inorganic components present, consequently elucidating them is one of the tasks of greatest significance facing wine analysis. It is, on the other hand, of unique importance from the economic viewpoint to make sure and keep a continuous check on whether wine qualities are satisfactory enough, taking the trend into consideration that nowadays among products for human consumption it is solely those that show a high likelihood to succeed on the market in the long run that manage to satisfy quality requirements of gradually increasing demands. Research into food analytic on the other hand, plays a considerably significant role in origin protection which is an issue of particular importance in the case of a wine-growing area of such long tradition. During the course of the investigation the answer was sought to the question of how qualitative and quantitative relations of volatile organic and metal components present in traditional wines produced in the wine-growing area depend on the vintage, the location on which it is grown, as well as the type of wine grape and to what extent these are characteristic of wines of given type and vintage.     

Volatile compounds as markers of ageing in Tempranillo red wines from La Mancha D.O. stored in oak wood barrels

Solid-phase extraction cartridges (SPE)-GC/MS method was used to analyse red wines aromas. The matrix effect was studied with chemicals standard prepared in synthetic wines with water/alcohol solutions (12% ethanol, v/v) following the procedure proposed. The method offers good reproducibility since the relative standard deviations (RSD%) for the volatile compounds levels were less than 9%. This method was used to differentiate the aroma of one hundred mono-varietal young, crianza, reserva and gran reserva La Mancha D.O. wines (cv. Tempranillo) on the basis of oak barrel contact period. Samples were checked at ten time points over 36 months. Sixty important wine odorants, such as volatile phenols, vanillin derivatives, lactones, norisoprenoids, benzene compounds, esters and terpenols, can be quantitatively determined in a single run. Results showed significant quantitative differences in the volatile profiles of wines depending on the length of time in contact with wood, even in wines belonging to the same commercial category. Stepwise multiple linear regression (SMLR) was used to obtain a model that predicted the time of barrel ageing to which wines were submitted in relation with the wine volatile composition. A successful function based on eight compounds with a mean deviation of 0.37 months in the predictions, was obtained.     

中华猕猴桃果实香气成分的GC-MS分析

采用溶液萃取法，提取“早鲜”猕猴桃果实中的香气成分，经气相色谱－质谱联机分析，鉴定出45个香气组分，占总峰面积的95．9％，其相对含量，以棕榈酸，辛酸，油酸，3－羟基丁酸乙酯，（Z，Z）－9，12－十八二烯酸，1，2，4－三羟基－（对）－萜烷，（E）－2－己烯醛，1，2－苯二甲酸双（2－甲氧基乙基）酯，硬脂酸，2－己烯醛等为主。     

喷气燃料中胶质化合物的质谱分析

喷气燃料中的不安定组分对燃料安定性影响很大,不安定组分主要集中在胶质化合物中,胶质化合物的存在会增加燃烧积炭,影响航空发动机的正常使用[1-2]。不安定组分含量极少,必须通过一定条件的分离和富集才能进行分析和评价。本文采用中性氧化铝吸附和极性溶剂脱附的方法分离制备