固相微萃取与同时蒸馏萃取法分析香精成分比较

分别采用同时蒸馏萃取法与固相微萃取法对烟草香精中的香味成分进行萃取 ,再用气相色谱 /质谱联用法和气相色谱法进行了定性和定量 ,并对这 2种萃取方法鉴定出的化学成分、重复性和定量值进行了比较。结果显示 :同时蒸馏萃取法具有良好的重复性和较高的萃取量 ,适合于烟用香精香味成分的定量分析 ;固相微萃取法具有快速简便、不使用溶剂和样品检测非破坏性等优点 ,适合于香精的剖析定性。     

顶空-液相微萃取在烟用香精分析中的应用

考察了萃取溶剂、萃取剂体积、样品预平衡时间、萃取时间以及萃取温度对顶空-液相微萃取(HS-LPME)的影响,建立了XJ1香精样品的HS-LPME前处理方法,即样品在室温(20℃)下预平衡20min后,用2μL正丙醇顶空萃取20min,并采用GC法分析了HS-LPME萃取液中的挥发性组分。结果表明,XJ1香精中6种挥发性组分:柠檬烯、6-甲基-5-庚烯-2-酮、苯甲醛、芳樟醇、苯甲醇和2-乙酰吡咯的回收率在86.3%～107.7%之间;相对标准偏差(RSD)<4.32%;检出限达0.16～3.02μg/mL。HS-LPME适用于XJ1香精挥发性组分的快速分析。     

固相微萃取在气相色谱-质谱联用检测纺织品中有机磷农药的应用

针对纺织品中微量甚至痕量有机磷农药残留难于采集和制备，进而给分析检测带来较大误差的问题，将固相微萃取（SPME）技术应用在气相色谱-质谱（GC—MS）联用法中，以棉纺织品为例，对其中常见的马拉硫磷、甲基对硫磷和喹硫磷3种有机磷农药进行吸附富集、萃取和检测。测试结果表明，采用100μm的聚二甲基硅氧烷（PDMS）纤维对样品萃取30min，在GC仪器的进样口热解脱附180S后，即可进行GC—MS定量检测，线性范围0．1～500μg／L，检出限低于0．05μg／L，实际样品平均回收率介于94．5％～96．2％之间，相对偏差（R.S．D）介于9％～13％之间，说明SPME法是一种简便可行的有机磷农药的样品预处理方法。     

固相微萃取GC-MS技术在梨香气成分分析中的应用研究

用固相微萃取技术(SPME)提取梨果实中香气成分,对影响萃取效果的因素及实验参数进行探讨、优化,确定了最佳萃取条件,同时结合GC/MS对提取的成分进行分析鉴定,为梨果实中香气成分的快速测定提供技术保证。     

固相微萃取气相色谱检测纺织品中异常气味

采用固相微萃取顶空进样技术和气相色谱对纺织品中的异常气味进行了分析，探讨了异常气味样品的采样方法和分析条件，利用70μm乙烯二醇一二乙烯基苯共聚物（CW／DVB）萃取膜对异常气味样品进行了多次取样分析，获得了霉味、高沸点的石油味等气相色谱的指纹图谱；研究发现组成气味的气体的种类不同，其气相色谱的指纹图谱也有所不同，多次分析同一种气味样品的色谱图有较好的相似性。从总的取样及分析结果看，利用该技术对纺织品异常气味进行分析研究的应用前景较好。     

固相微萃取在食品挥发性组分测定方面研究进展

固相微萃取是一种新颖的样品前处理与富集技术,其克服传统预处理方法几乎所有缺点,可与多种色谱技术联用;对食品风味组分检测大多采用固相微萃取与GC、GC–MS等技术联用,而新涂层开发、与其它分析方法联用是固相微萃取测定挥发性组分研究方面重要方向。     

分散固相萃取-气相色谱-质谱法测定鸡肉香精中17种邻苯二甲酸酯

目的建立同时测定鸡肉香精中17种邻苯二甲酸酯的分析方法。方法经水预处理后的鸡肉香精样品,用乙腈饱和的正己烷提取,并用正己烷饱和的乙腈反提取除去提取液中残留的大部分油脂,用分散固相萃取进行净化,最后用气相色谱-质谱(GC-MS)进行分析。结果 17种邻苯二甲酸酯在0.05~10 mg/L之间线性关系良好,检出限为0.05 mg/kg。17种邻苯二甲酸酯回收率在72.8%~94.7%之间,RSD为1.0%~16.3%。结论本方法简单、试剂用量少,具有绿色环保的优势。在最优实验条件下,此方法有效地降低了检测限,提高了灵敏度,具有良好的回收率。     

固相微萃取虾味香精中风味化合物的研究

以虾下脚料酶解液、L-精氨酸、L-丙氨酸、还原糖、硫胺素盐酸盐等为原料制备热反应虾味香精;采用固相微萃取技术并结合GC-MS检测技术对产物进行分析,总共获得61种挥发性化合物,尤其是鉴定出了二甲基二硫醚、吡嗪、3-甲基噻唑、2,5-二甲基吡嗪、2,6-二甲基吡嗪、2,3-二甲基吡嗪、三甲基吡嗪、二甲基三硫醚、甲基吡嗪、苯乙酮、噻唑醇、2-呋喃甲醇等文献报道对虾香味有贡献的化合物。     

固相微萃取(SPME)在茶叶香气分析中的应用

茶叶香气是影响茶叶品质的重要因子之一,其组成复杂且在茶叶中的含量低。固相微萃取作为目前茶叶香气的富集手段,具有操作简便快速等优点,是茶叶香气研究的热点。本文综述了近年来茶叶香气特征和固相微萃取(SPME)技术及其在茶叶香气分析中的应用。     

固相微萃取(SPME)在茶叶香气分析中的应用

茶叶香气是影响茶叶品质的重要因子之一,其组成复杂且在茶叶中的含量低。固相微萃取作为目前茶叶香气的富集手段,具有操作简便快速等优点,是茶叶香气研究的热点。本文综述了近年来茶叶香气特征和固相微萃取(SPME)技术及其在茶叶香气分析中的应用。      

Analysis of crab meat volatiles as possible spoilage indicators for blue crab (Callinectes sapidus) meat by gas chromatography–mass spectrometry

Traditionally crab meat spoilage has been evaluated using sensory panels. A method was developed using solid-phase microextraction–gas chromatography–mass spectrometry (SPME–GC–MS) to examine the aroma profile of blue crab (Callinectes sapidus) for chemical indicators of spoilage. The chemicals found to correlate best with spoilage were trimethylamine (TMA), ammonia, and indole over a period of 7 days. In addition, chemicals previously not identified in the aroma profile of blue crab were tentatively detected. Scan mode of the mass spectrometer was used to qualitatively determine compounds extracted from the volatile profile of spoiling blue crab by the SPME fiber. Selected ion monitoring (SIM) mode of the mass spectrometer improved resolution, identified compounds at low concentrations, and allowed spoilage related compounds to be detected in one chromatographic run without sample heating. TMA increased linearly. A significant difference in TMA concentrations were found for day 0 and day 4 samples. Indole concentrations corresponded well with sensory and microbial evaluations, in early, mid, and highly spoiled crab meat samples.     

即食豆干加工过程中挥发性风味物质的研究

为研究加工工艺对即食豆干挥发性风味物质的影响,采用固相微萃取(SPME)结合气相色谱-质谱联用(GC-MS)对即食豆干各工艺阶段风味物质进行定性和定量分析。结果表明:在原料、卤制、油炸和杀菌的样品中分别检测出44种、62种、56种、53种物质,含量分别是2560.84μg/kg、3168.53μg/kg、2277.82μg/kg、937.64μg/kg,醛类、醇类、酮类、烷烃类以及其它类构成即食豆干的风味成分;卤制能降低腥味醇类物质含量,增加香气醛类、酮类和其它类物质的含量,使豆干具有焦糖香气,甜香及香辛料香;油炸后具有特征香气的醛类、酮类和醇类等物质含量均有所下降,特征香气成分损失严重;特征风味物质在杀菌后进一步损失,且最终产品中重要豆腥味物质正己醛、1-辛烯-3醇的相对含量(32.63%)较高。因此,即食豆干的加工工艺可进行适当改良,以期获得更高品质的即食豆干产品。     

An accurate quantitative method for the analysis of terpenes in milk fat by headspace solid-phase microextraction coupled to gas chromatography–mass spectrometry

HS-SPME analysis of terpenes does usually have inherent quantification problems when working with complex samples, especially due to the matrix effect of the substrate or the calibration solution. Three different terpene carrier matrices were compared: methanol, synthetic oil and milk fat obtained by centrifugation from milk cream. Considerable differences in calibration sensitivity parameters were observed depending on the matrix used and on the type of terpene standard analysed. For milk sample quantification purposes internal standard method was preferred using milk fat as calibration matrix. Linearity range, repeatability, recovery and limits of detection and quantification were determined. Validation parameters were different depending on the concentration and molecular structure of each terpene analysed, particularly between mono- and sesquiterpenes. The method was useful to determine in an accurate manner the terpene content in milk samples from pasture fed animals, and it will help to establish objective terpene levels to differentiate milks from specific production systems.     

气相色谱/质谱法测定烟用香精和料液中的烟碱含量

为了测定复杂组分烟用香精和料液中的烟碱含量,建立了气相色谱/质谱联用法。应用建立的方法对10个香精样品和10个料液样品进行了检测。结果表明:在0.9242～46.2080μg/mL浓度范围内线性良好,相关系数r为0.99992,3个加标水平的回收率在97.54%～99.14%之间,相对标准偏差(RSD)为1.34%。该方法灵敏度高,定性定量结果可靠,可用于烟用香精和料液中烟碱的测定。     

SPME followed by GC–MS: a powerful technique for qualitative analysis of honey volatiles

Volatile compounds from 40 honey samples of different botanic origin were analyzed by SPME followed by GC–MS. In order to obtain complementary data for an overall characterization of honey aroma, two different SPME fiber coatings (polyacrylate and carboxen/polydimethylsiloxane) were employed. The use of both fibers with a single chromatographic column afforded the identification or characterization, based on GC retention and mass spectral data, of a total of 193 volatile components. A total of 166 honey volatiles were characterized (146 identified) from CAR/PDMS data, this fiber being the most appropriate for isolation of low molecular weight compounds. Polyacrylate fiber was better for extraction of polar semivolatiles, allowing to identify 120 compounds and to characterize 132. Besides typical nectar components such as limonene, linalool, etc., different compounds from fermentation (ethanol and 2,3-butanediol), processing (furan derivatives), hive treatment (thymol), etc. were detected. Although many volatiles were common to most honey samples analyzed, other seemed to be characteristic of certain honey types. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Volatile analysis of spoiled,artisan-type,modified-atmosphere-packaged cooked ham stored under different temperatures

Metabolite production due to bacterial outgrowth and oxidation phenomena lead to spoilage development of cooked ham. Artisan-type products, with low salt concentrations and a minimum of additives, are particularly sensitive. Cold chain variations related to distribution and consumer habits have a negative influence on the shelf-life. In this study, sliced, modified atmosphere packaged artisan-type cooked ham was stored at different temperatures (4, 7, 12, and 26 °C). The evolution of volatiles over time for the different storage temperatures was monitored with static headspace gas chromatography/mass spectrometry (SH–GC–MS). The latter method was compared to solid phase microextraction (SPME). Several of the detected compounds could be ascribed to bacterial glucose and amino acid metabolism and their production was related to the storage temperature. The compounds 3-methyl butanol and ethanol were related with bacterial cell growth. Maillard-derived compounds, leading to the formation of furans, probably originated from endogenous reactions during cooking. Several detected aliphatic compounds probably originated from fatty acid oxidation reactions, including thermal fat degradation, chemical auto-oxidation, and enzymatic β-oxidation.     

超高压处理对黑莓酒香气成分的影响

运用超高压技术处理黑莓酒以期改善其香气品质,并采用固相微萃取与气相色谱-质谱联用对不同超高压条件处理的黑莓酒挥发性香气成分进行检测,探究超高压处理对黑莓酒香气成分的影响及作用机理.结果表明:经超高压处理的黑莓酒香气种类与未处理样品相同,但含量发生较大变化,200MPa处理20min的黑莓酒醇类、酯类和醛类无显著变化(p＞0.05),酸类减少了7.44％;600MPa处理20min的黑莓酒醇类、酯类分别增加了4.63％、13.38％,醛类、酸类无显著变化(p＞0.05);400MPa处理20min的黑莓酒醇类、酯类和醛类分别增加了4.89％、43.04％和1.12％,酸类减少了11.28％,整体香气趋向柔和、协调、饱满,达到改善黑莓酒香气品质的目的.     

Study of the volatile compounds useful for the characterisation of fresh and frozen-thawed cultured gilthead sea bream fish by solid-phase microextraction gas chromatography–mass spectrometry

A simple method, based on solid-phase microextraction gas chromatography–mass spectrometry, was developed for the study of the aromatic profile of cultured gilthead sea bream fish during frozen storage. The method was applied to the study of the volatile profile of fresh and frozen-thawed Italian and Spanish cultured gilthead sea bream fish over 266 days of frozen storage. Variations in the chromatographic responses of a number of volatile compounds during storage were detected and the observed differences evaluated on a biochemical basis. Correlations with oxidation parameters, e.g. peroxide value and thiobarbituric acid-reactive substance indices, indicated 1-octen-3-ol, 1-penten-3-ol, and Z-4-heptenal as markers for the differentiation between fresh and frozen-thawed fish.     

基于不同发酵方法制作的曲拉中挥发性风味物质分析

采用顶空-固相微萃取（HS-SPME）方法对传统自然发酵的曲拉与商品发酵剂制作的曲拉样品进行预处理,利用气相色谱-质谱法（GC-MS）检测样品中的挥发性风味成分。经NIST14质谱数据库检索结合文献对照,从传统自然发酵的曲拉中检出29种挥发性风味成分,商品发酵剂制作的曲拉中检出53种,这些挥发性成分中主要包括酸类、醇类、酮类、醛类、酯类、烃类、芳香类。不同发酵方法制作的曲拉中风味物质的种类及含量都存在一定的差异性,这也是使用相同原料不同发酵方法制作的曲拉产生特别的风味的主要原因。