顶空固相微萃取-气相色谱-质谱法分析芝麻香精的挥发性成分

采用顶空固相微萃取-气相色谱-质谱法分离和鉴定芝麻香精中挥发性成分,用归一化法测定其相对含量。为使固相微萃取达到更高的效率,选用50/30μm DVB-CAR-PDMS的固相萃取头,萃取温度及时间为60℃和1h。两种芝麻香精中分别鉴定出31和28种香气成分,其中含量较高的几类物质分别为吡嗪类、呋喃类、吡啶类、酮类和酚类物质。1号香精中的主要香气化合物为:1,6-二氢-咪唑并[4,5-d]咪唑、甲基吡嗪、3,5-二甲基苯酚、糠醛、2,6-二甲基-4-氨基吡啶和5-甲基-2-呋喃甲醛。2号香精中的主要香气化合物为:2,3-二甲基吡嗪、2-糠酸糠酯、4-氨基吡啶、3,5-二甲基苯酚、乙酰基吡嗪和糠醛。     

气相色谱-质谱对天然酿造酱油与配制酱油香气成分的分析比较

利用蒸馏萃取/气相色谱-质谱(SDE/GC-MS)方法对酱油香气成分进行了分析,在4种不同工艺生产的酱油中共鉴定出51种化学成分,其中醇类12种、酚类5种、醛酮8种、酸类6种、酯类7种、杂环化合物类13种,同时发现,3种酿造酱油中的共有成分为35种.不同工艺生产的酿造酱油中醇、酚、醛酮、酯类物质的种类均比配制酱油多1倍以上,酸类物质的总含量也远大于配制酱油,但配制酱油的杂环类风味物质比较丰富,主要为体现烤香风味的吡嗪类化合物.乙醇、2-甲基丙醇、3-己醇、3-甲硫基丙醇、苯乙醇、乙烯基-2-甲氧基-苯酚、4-乙基-苯酚、α-亚乙基-苯乙醛、香草醛、2-羟基丙酸乙酯、乙酸乙酯、乙酸苯甲酯、亚油酸乙酯、5-甲基糠醇、3-苯基呋喃为酿造酱油的特有成分.构成酱油特征香气成分的4-乙基愈创木酚、糠醇、糠醛等物质的含量在配制酱油中也相对较少.这正是酿造酱油与配制酱油风味不同的原因之一.该文研究结果验证了生产酿造酱油时不同原料不同工艺会对风味物质产生影响.     

鸡骨素及其酶解液的美拉德反应产物挥发性风味成分比较分析

利用固相微萃取/气相色谱-质谱(SPME/GC-MS)联用与电子鼻(E-Nose)嗅探技术对鸡骨素美拉德反应产物(MRPs1)及鸡骨素酶解液美拉德反应产物(MRPs2)中的挥发性风味成分进行比较分析。在两种产物中共鉴定出77种挥发性化学成分,其中醇类18种、醛酮类23种、酸类3种、酯类10种、杂环类7种及其他类16种,两种产物中共有成分26种。与MRPs1相比,MRPs2中醛酮、杂环类化合物的相对含量较高,但前者的酯类物质含量更为丰富。(E)-2-辛烯-1-醇、(6Z,9Z)-十五碳二烯-1-醇、苯甲醛、辛醛、6-甲基-5-庚烯-2-酮、2-乙基-3-羟基-4(4H)-吡喃酮、2,3,5-三甲基-6-乙基吡嗪、2-[(甲基二硫基)甲基]呋喃构成了MRPs2的特有成分,γ-丁位十二内酯为MRPs1的特有成分。在两种反应产物中,除4-甲基-5-羟乙基噻唑的相对含量均较高外(MRP1相似文献   

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。     

固相微萃取-气相色谱-质谱联用结合嗅觉检测法鉴定血橙汁中的香气活性化合物

采用固相微萃取-气相色谱-质谱法(SPME-GC-MS)和嗅觉检测法对血橙汁中的挥发性物质进行分析,确定了血橙汁中的香气活性化合物。采用二乙烯基苯/碳分子筛/聚二甲基硅氧烷共聚物(DVB/CAR/PDMS)萃取头在40 ℃条件下顶空萃取40 min。通过气相色谱-质谱联用结合保留指数,在所萃取的血橙汁的挥发性化合物中共鉴定出46种化合物。通过嗅觉检测法检测出34种具有气味的化合物,其中23种被定性。结果表明,对血橙汁香气起主要贡献的化合物是丁酸乙酯、辛醛、γ-松油烯、芳樟醇、4-乙酰基-1-甲基环己烯、癸醛、(-)-香芹酮、乙酸香叶酯、巴伦西亚桔烯以及保留指数分别为1020,1143,1169和小于800的4个未知化合物,这些香气强度较高的化合物的总相对含量为7.22%。     

顶空固相微萃取-气相色谱-质谱法快速测定酱油中的挥发性风味成分

建立了一种快速简便地测定酱油中挥发性风味成分的顶空固相微萃取（HS-SPME）-气相色谱-质谱法(GC-MS)。以2-辛醇为内标,考察了萃取头、萃取时间、离子强度、萃取温度对酱油样品中挥发性风味物质萃取的影响。该方法对酱油中常见挥发性风味成分的测定有良好的重复性和回收率,对常见挥发性物质的定量比较准确。优化的HS-SPME条件为：涂层厚度为85 μm聚丙烯酸酯(PA)萃取纤维头,于45 ℃、NaCl质量浓度为250 g/L下对酱油样品顶空吸附40 min,于250 ℃下解吸2 min后进行GC-MS分离鉴定。酱油样品的分析结果表明,其挥发性风味物质中含量较高的是醇、酸、酯和酚类,此外还有一些羰基化合物和杂环化合物。     

顶空固相微萃取-气相色谱-质谱法测定小米黄酒风味成分

为全面了解小米黄酒风味成分的构成和气味特征,优化了85μm聚丙烯酸酯(PA)、100μm聚二甲基硅氧烷(PDMS)、75μm碳分子筛(CAR)/PDMS、50/30μm二乙烯基苯(DVB)/CAR/PDMS萃取头提取小米黄酒风味成分的条件,采用顶空固相微萃取(headspace solid phase microextraction,HS-SPME)-气相色谱-质谱法(GC-MS)对风味成分进行定性、定量分析,并计算气味活性值(odor active value,OAV),同时利用OAV分析风味成分的气味特征和气味强度。结果显示:不同萃取头的最优萃取条件为样品量8 mL、萃取时间40 min、萃取温度60℃、NaCl添加量1.5 g。小米黄酒风味成分由醇、酯、含苯化合物、烃、酸、醛、酮、烯、酚和杂环类化合物构成,醇为主要风味成分。通过OAV确定了苯乙醇、苯乙烯、2-甲基萘、1-甲基萘、苯甲醛、苯乙醛、2-甲氧基-苯酚为小米黄酒气味特征成分,苯基乙醇、苯乙醛对气味贡献最大。PA和PDMS萃取头分别对极性和非极性化合物具有较好的吸附效果,CAR/PDMS和DVB/CAR/PDMS萃取头对中等极性化合物具有较好的吸附效果。该研究全面了解了小米黄酒风味成分的构成,为其产品开发及品质控制提供理论了依据。     

固相微萃取-气相色谱-质谱法测定牡丹花挥发油中各成分

采用固相微萃取-气相色谱-质谱法分离和测定牡丹花中挥发油成分,用归一化法测定其相对含量。为使固相微萃取达到更高的效率,选用50/30μm PDMS/DVB/CAR的固相萃取头,萃取温度及时间为45℃和40min。共检出38种化合物,总质量分数为2 481.34ng·g-1。其中乙酸己酯、香茅醇、香叶醇和丙酸香叶酯等物质为构成牡丹花的特征香气的重要成分。     

顶空-固相微萃取-气相色谱法检测可可麦汁中吡嗪类化合物

建立了顶空-固相微萃取(HS-SPME)-气相色谱快速测定可可麦汁中3种吡嗪类物质(2,5-二甲基吡嗪、2,3,5-三甲基吡嗪和2,3,5,6-四甲基吡嗪)的方法.选择不同的固相微萃取头对萃取温度和时间进行优化,所得最佳萃取条件为:在60℃下,采用75 μm CAR/PDMS萃取头对麦汁样品萃取40 min.本方法的检出限(S/N=3)为0.023～ 0.056 μg/L,线性范围1～500 mg/L;相对标准偏差为3.6％～6.4％;回收率为95.4％～102.7％.本方法应用于样品检测,发现可可麦汁中吡嗪的浓度与原料中可可粉的添加量正相关,显示了很好灵敏性.     

顶空固相微萃取-气相色谱/质谱分析艾叶中的易挥发性成分

采用顶空固相微萃取(HS-SPME)与气相色谱/质谱(GC/MS)联用方法对艾叶中易挥发性成分进行了分析,并通过单因素和正交试验对影响HS-SPME的条件进行优化,确定了HS-SPME的最优参数为:50/30μm DVB/CAR/PDMS固相微萃取头、样品用量0.8g、萃取温度75℃、萃取时间50min、平衡时间30min、解吸4min。经GC/MS分析,共检出196种化合物,利用质谱解析结合保留指数定性确定结构132种,占易挥发性成分总量的94.01%。其中主要易挥发性成分是3-氨基吡唑、桉油精、β-杜松烯、顺-β-松油醇、3-甲基-2-丁烯酸-4-硝基苯基酯、3,6,6-三甲基-1,5-庚二烯-4-醇、6-甲基-3-(1-异丙基)-2-环己烯-1-酮、3-甲基-2-丁烯酸环丁酯。本文结果为艾叶易挥发性成分及其开发利用提供了一定的理论依据。     

Rapid determination of volatile constituents in safflower by microwave distillation and simultaneous solid-phase microextraction coupled with gas chromatography-mass spectrometry

In this paper, microwave distillation and solid-phase microextraction coupled with gas chromatography-mass spectrometry (MD-SPME/GC-MS) was developed for the analysis of essential components in safflower. Using the MD-SPME technique, the isolation, extraction and concentration of volatile compounds in safflower were carried out in only one step. Some parameters affecting the extraction efficiency such as SPME fiber coating, microwave power, irradiation time and the volume of water added were optimized. The optimal experiment parameters obtained were: 65 microm CW/DVB SPME fiber, a microwave power of 400 W, an irradiation time of 3 min and water volume of 1 mL. The proposed method has been compared with conventional steam distillation (SD) for extraction of essential oil compounds in safflower. Using MD-SPME followed by GC-MS, 32 compounds in safflower were separated and identified, which mainly included paeonol, alpha-asarone, beta-asarone, 1-methyl-4-(2-propenyl)-benzene and diethenyl-benzene, whereas only 18 compounds were separated and identified by conventional SD followed by GC-MS. The relative standard deviation (R.S.D.) values of less than 10% show that the proposed method has good reproducibility. The results show that MD-SPME/GC-MS is a simple, rapid, effective method for the analysis of volatile oil components in safflower.     

Development of a headspace solid-phase microextraction-gas chromatography-mass spectrometry method for the identification of odour-causing volatile compounds in packaging materials

A method for the identification of volatile organic compounds in packaging materials is presented in this study. These compounds are formed by thermooxidative degradation during the extrusion coating process in the manufacture of packaging. Headspace solid-phase microextraction (HS-SPME) was used as sample preparation technique prior to the determination of the volatile organic compounds by gas chromatography-mass spectrometry (GC-MS). The effects of extraction variables, such as the type of fibre, the incubation temperature, the pre-incubation time, the size of the vial and the extraction time on the amounts of the extracted volatile compounds were studied. The optimal conditions were found to be: carboxen-polydimethylsiloxane 75 microm fibre, 5 min of pre-incubation time, 100 degrees C of incubation temperature, 20-ml vial, and 15 min of extraction time. The chromatograms obtained by HS-SPME and static headspace extraction were compared in order to show that the HS-SPME method surpasses the static headspace method in terms of sensitivity. Twenty-five compounds were identified including carbonyl compounds (such as 3-methyl-butanal, 3-heptanone or octanal), carboxylic acids (such as pentanoic acid or hexanoic acid) known as odour causing compounds and hydrocarbons (such as decane, undecane or dodecane). Finally, the method was applied to different packaging samples (one odour-unacceptable, two odour-acceptable, and three odourless samples) and to the raw materials in order to find out the odour-responsible volatile organic compounds and their source.     

Development of gas chromatography-mass spectrometry following microwave distillation and simultaneous headspace single-drop microextraction for fast determination of volatile fraction in Chinese herb

In this work, for the first time, microwave distillation (MD) coupled with simultaneous headspace single-drop microextraction (HS-SDME) was developed for the determination of the volatile components in the Chinese herb, Artemisia capillaris Thunb. The volatile components were rapidly isolated by MD, and simultaneously extracted and concentrated by using a dodecane microdrop. The volatile oil extracted in the microdrop solvent was analyzed by gas chromatography-mass spectrometry (GC-MS). The experimental parameters of solvent selection, microdrop volume, microwave power, irradiation time and sample amount were investigated, and the method precision was also studied. The optimal parameters were extraction solvent of dodecane, solvent volume of 2.0 microL, microwave power of 400 W, irradiation time of 4 min, and sample amount of 2.0 g. Thirty-five volatile compounds present in Artemisia capillaris Thunb. were identified by using the proposed method, which were identical with those obtained by the conventional steam distillation method. The experimental results showed that MD-HS-SDME is a simple, rapid, reliable, and solvent-free technique for the determination of volatile compounds in Chinese herbs.     

Determination of volatile organic compounds generated from fresh, white and red Panax ginseng (C. A. Meyer) using a direct sample injection technique

Ginsenosides are regarded as the main active, non-volatile components of Panax ginseng (C. A. Meyer). However, throughout the long history of ginseng research, there has been virtually no report describing its volatile flavor compounds. A solvent-free procedure for the determination of volatile flavor compounds generated from fresh, white and red Panax ginseng (C. A. Meyer) using solvent-free solid injection (SFSI) coupled with gas chromatography-mass spectrometry (GC-MS) detection is described here. At no point in the SFSI technique were the extraction conditions optimized. Rather, the experimental variables including various sample preparations (fresh, oven-dried and freeze-dried), injector temperatures (100, 150, 200, 250 and 300 degrees C), and preheating times (3, 5, 7, 10 and 15 min), were predicated on the experience of the authors. A total of 47 compounds were identified in various forms of ginseng. Among the compounds identified in the sample, fresh ginseng was characterized by a high proportion of 3-acetyl-1-(3,4-dimethoxyphenyl)-5-ethyl-4,5-dihydro-7,8-dimethoxy-4-methylene-3H-2,3-benzodiazepine (64.24%) and 23,24-dinor-3-oxolean-4,12-dien-28-oic acid (21.42%); 2-furanmethanol (20.26%) and 3-hydroxy-2-methyl-4H-pyran-4-one (17.95%) were detected as the major components in white ginseng while the main components of the red ginseng were found to be 1,2-benzenedicarboxylic acid dibutyl ester (16.27%) and 2-furanmethanol (13.82%). SFSI is a solvent-free, rapid and simple sample preparation technique based on direct vaporization. There is no dilution or contamination with solvent or its impurities and no loss of quickly eluted components was observed in the solvent peak.     

气质联用法分析澳洲坚果壳的挥发性成分

分别建立了微波萃取和顶空直接进样GC/MS法对澳洲坚果壳的挥发性成分进行了分析。从澳洲坚果壳共分离鉴定了37个挥发性成分,包含烯烃、酸类、醛类、酮类、内酯类等,且澳洲坚果壳乙醇提取物具有令人愉悦的香味,其香气风格与原样迥异,具有成为香精香料来源的潜质。     

不同方法提取香椿芽挥发油的比较研究

采取超-临界CO2萃取、乙醚超声波萃取、乙醚微波萃取和微波水蒸气萃取4种方法提取香椿芽挥发油,利用气相色谱.质谱联用技术,分析了挥发油的化学组成,并进行了比较.结果表明:4种提取方法得到的挥发油的化学组分存在差异,其中含有20种相同的化合物,一种未鉴定,其余19种主要是相对分子质量为204.19的倍半萜类化合物和相对分子质量在240～280之间的化合物,但各组分的含量有差异.     

Rapid Extraction of Volatile Compounds Using a New Simultaneous Microwave Distillation: Solvent Extraction Device

Simultaneous distillation–extraction (SDE) is routinely used by analysts for sample preparation prior to gas chromatography analysis. In this work, a new process design and operation for microwave assisted simultaneous distillation–solvent extraction (MW-SDE) of volatile compounds was developed. Using the proposed method, isolation, extraction and concentration of volatile compounds can be carried out in a single step. To demonstrate its feasibility, MW-SDE was compared with the conventional technique, SDE, for gas chromatography-mass spectrometry (GC-MS) analysis of volatile compounds in a fresh aromatic herb, Zygophyllum album L., a wild salty desert herb belonging to the family Zygophyllaceae. SDE method required a long time (3 h) to isolate the volatile compounds, and large amounts of organic solvent (200 mL of hexane) for further extraction, while MW-SDE needed shorter time (only 30 min) to prepare the sample, and less amount of organic solvent (10 mL of hexane). These results show that MW-SDE–GC-MS is a simple, rapid and solvent-less method for the determination of volatile compounds from aromatic plants.     

微波蒸馏-固相微萃取-气相色谱-质谱-嗅觉检测器联用分析鳙鱼鱼肉中的挥发性成分

用微波蒸馏(MD)-固相微萃取装置(SPME)提取鳙鱼鱼肉中的挥发性成分,利用气相色谱-质谱联用仪(GC-MS)对气味化合物成分进行了定性分析,同时利用嗅觉检测器鉴别了部分挥发性物质的气味特征。实验中优化了MD的操作条件(加热功率、加热时间及载气流速等)、SPME参数(萃取头种类、萃取温度、萃取时间、无机盐离子浓度及搅拌速率等)。通过NIST 02质谱数据库检索共定性确定出鳙鱼鱼肉挥发性成分中的53种化合物,其中主要为 C6~C9 的羰基化合物和挥发性醇类。经过嗅觉检测器分析,这些成分分别具有青草味、鱼腥味、泥土味等气味特征,其协同作用构成了鳙鱼鱼肉特殊的鱼腥味、泥腥味。该方法可用于水产品中挥发性成分的分析,并可为不良风味化合物的定量研究提供参考。     

Rapid Analysis of the Essential Oil of Acorus tatarinowii Schott by Microwave Distillation, SPME, and GC-MS

The dry rhizome of Acorus tatarinowii Schott is a traditional Chinese medicine (TCM) which has been used to treat many diseases, for example epilepsy, for thousands of years. In this work, microwave distillation and simultaneous solid-phase microextraction (MD-SPME) were used for analysis of the essential oil in the fresh leaves of Acorus tatarinowii. Isolation, extraction, and concentration of the volatile constituents of the leaves can be completed rapidly, in a single step, by use of MD-SPME; the compounds can then be analyzed by gas chromatography-mass spectrometry (GC-MS). MD-SPME conditions, including microwave power, irradiation time, and SPME fiber coating, were studied. By use of MD-SPME-GC-MS twenty-nine compounds were identified, for the first time, in the essential oil of the plant leaves; the compounds were the same as those in the rhizomes. This suggests the leaves of the plant might be used as a TCM. To demonstrate the feasibility of the method, conventional steam distillation (SD) was also used for extraction of the essential oil from the leaves. The same compounds, in similar amounts, were identified by both methods, confirming the MD-SPME method is highly reliable. Compared with SD, MD-SPME required less time (only 2 min), less sample (1.0 g), and no organic solvent. These results are indicative of the suitability of MD-SPME-GC-MS for simple, rapid, and solvent-free analysis of plant essential oils.     

Rapid analysis of the essential oil components of dried Zanthoxylum bungeanum Maxim by Fe2O3‐magnetic‐microsphere‐assisted microwave distillation and simultaneous headspace single‐drop microextraction followed by GC–MS

In this work, microwave distillation assisted by Fe₂O₃ magnetic microspheres (FMMS) and headspace single‐drop microextraction were combined, and developed for determination of essential oil compounds in dried Zanthoxylum bungeanum Maxim (ZBM). The FMMS were used as microwave absorption solid medium for dry distillation of dried ZBM. Using the proposed method, isolation, extraction, and concentration of essential oil compounds can be carried out in a single step. The experimental parameters including extraction solvent, solvent volume, microwave power, irradiation time, and the amount of added FMMS, were studied. The optimal analytical conditions were: 2.0 μL decane as the extraction solvent, microwave power of 300 W, irradiation time of 2 min, and the addition of 0.1 g FMMS to ZBM. The method precision was from 4 to 10%. A total of 52 compounds were identified by the proposed method. The conventional steam distillation method was also used for the analysis of essential oil in dried ZBM and only 31 compounds were identified by steam distillation method. It was found that the proposed method is a simple, rapid, reliable, and solvent‐free technique for the determination of volatile compounds in Chinese herbs.