Profile of Volatile Compounds in 11 Brandies by Headspace Solid-Phase Microextraction Followed by Gas Chromatography-Mass Spectrometry

ABSTRACT:  A headspace solid-phase microextraction (HS-SPME) method coupled with gas chromatography-mass spectrometry (GC-MS) was applied for the qualitative or semiquantitative characterization of brandy volatiles. SPME variables (SPME fiber, extraction temperature and time, and ethanol concentration) were optimized. A total of 144 compounds were from the brandies' volatiles, tentatively identified or identified by comparing mass spectra and retention indices of the standards or from literature. Of these, 57 are common to 11 brandies. They were mainly represented by esters and alcohols, such as 2-methyl propanol, 3-methyl butanol, 1-hexanol, ethyl octanoate, and ethyl decanoate, which were quantitatively determined. Chromatographic peaks were integrated using selective ion method (SIM) and the semiquantitative data analyzed using principal component analysis (PCA) and cluster analysis (CA) to study relationships between volatile composition and brandy. Eleven brandies were differentiated into 3 groups: 1 for Hennessy VSOP and XO samples, 1 for Changyu PEGASE VSOP and XO-1, 2, 3 samples, and the other for Changyu PEGASE brandy and VO, Taro brandy, Baiyang River brandy, and Wealth XO samples. The classification of groups is consistent with the brandy samples by variety and grade.     

应用SBSE-TDS-GC-MS方法快速分析葡萄酒中挥发性及半挥发性成分

采用固相萃取搅拌棒(SBSE)萃取葡萄酒中的挥发性及半挥发性成分,再用热脱附(TDS)-气质联用仪(GC-MS)进行分析。研究了不同萃取时间及不同浓度NaCl盐析作用对萃取效率的影响;并对影响热脱附的3个主要因素:热脱附温度、时间及冷阱收集温度进行了条件优化。在优化条件下,对方法的重现性进行考察,方法相对标准偏差RSD均小于10%(n=6)。用此方法测定了葡萄酒中46种挥发性及半挥发性化合物,其中酯类和酸类占很大部分,另还有一定量的醇和醛酮类物质,这些化合物反应了葡萄酒的香气特征。     

兴隆咖啡烘焙过程中香气物质的变化规律

本文利用顶空固相微萃取-气相色谱-质谱(HS-SPME/GC-MS)结合电子鼻对海南兴隆地区咖啡豆不同烘焙度分别为极浅度(JQ)、浅度(Q)、浅中度(QZ)、中度(Z)、中深度(ZS)、深度(S)、极深度(JS)和法式重度(FZ)的挥发性成分进行分析。结果表明:JQ到FZ分别检出61、68、72、72、72、68、70、70种,在JQ、Q和QZ时,挥发性物质主要为吡嗪类和酸类,呈现坚果味和酸味;在Z及ZS时,呋喃类、吡咯类和酮类等起主要作用,为焦糖味和烧焦味;而S、JS和FZ时,主要是酚类和吡啶类贡献烟熏味和愉悦的丁香味。电子鼻可分析不同烘焙度咖啡的香气差异,除LY2/g CT和LY2/AA外,其他4个传感器对8种不同烘焙度咖啡样品的响应值均有明显差异性。本研究明晰了海南兴隆地区咖啡豆烘焙过程中香气成分的变化规律,为兴隆咖啡的烘焙工艺改进提供理论支撑。     

温室鳖与池塘鳖肌肉和裙边挥发性风味成分的研究

采用顶空固相微萃取(HS-SPME)和气质联用技术研究了温室鳖、池塘鳖肌肉和裙边的挥发性风味成分.共鉴定出113种化合物,温室鳖肌肉含59种,池塘鳖肌肉含34种,温室鳖裙边含60种,池塘鳖裙边含50种.113种化合物中含芳香族化合物23种、醛类23种、醇类19种、酮类12种、N、S化合物10种、烷烃类10种、酯类8种、酸类5种、呋喃类化合物3种.     

Characterisation of volatile compounds of farmed soft‐shelled turtle (Pelodiscus sinensis) by solid‐phase microextraction and the influence of matrix pH on the release of volatiles

Although farming and consuming of soft‐shelled turtle has been practised for centuries, the aroma‐impact compounds in the meat have not been determined. Furthermore, matrix pH, usually changing during processing and storage stage, was rarely investigated for the influence on volatile profiles. To these aims, soft‐shelled turtle meat was subjected to different pH conditions and the potential volatile compounds were analysed under different extraction conditions by headspace solid‐phase microextraction (HS‐SPME). A total of forty‐three volatiles were identified; in which, nonanal, (E, E)‐2, 4‐heptadienal, octanal, decanal, hexanal, (E)‐2‐nonenal, heptanal, 1‐octen‐3‐ol and o‐xylene were assigned as aroma‐impact compounds by high relative odour activity value (ROAV). Overly basic or acidic pH significantly (P < 0.05) facilitated the release of volatiles under moderate extraction conditions. The total volatilisation increased by 30.1% to 298% in pH‐shifted samples, while the highest one was found in pH 2 or pH 11. However, the results of principal components analysis (PCA) demonstrated that increased extraction time or temperature hindered the pH enhancement.     

GC-MS法分析柠檬蒸馏酒与发酵酒挥发性风味物质

采用定量描述性感官评价法对柠檬发酵酒与蒸馏酒进行感官评定,检测其理化指标,并利用气质联用（GC-MS）技术分析其挥发性风味物质组分及含量。结果表明,2种柠檬酒口感接近,除涩味外,苦、酸、甜味无显著差异（P＞0.05）;总酸、还原糖和可溶性固形物含量差异均显著（P＜0.05）;通过GC-MS技术从柠檬发酵酒与蒸馏酒中分别检测出40种、33种挥发性风味物质,且均以酯类物质种类（20种、15种）及相对含量（53.63%、48.43%）最高。与柠檬发酵酒相比,除检测到酯类、醇类、酸类、醛类物质外,柠檬蒸馏酒中还检测到烷烃类、杂环类及烯类物质。     

阿根廷马黛茶与广东红茶挥发性成分比较分析

本研究以阿根廷马黛茶和广东红茶为研究对象,采用顶空固相微萃取-气质联用仪(HS-SPME-GC/MS),分析马黛茶和红茶的挥发性成分,探明其差异组分,明晰马黛茶的特征挥发性成分。结果表明:醇类是马黛茶(MD)和广东红茶中主要的挥发性成分种类。萜醇(24.34%)和萜酮(18.97%)是MD中主体挥发性成分,MD中香叶基丙酮(4.84%)相对含量高于优选5号红茶(YX5,1.14%)和大叶奇兰10号红茶(QL10,0.89%)。脂肪醛、萜醛、脂肪酮、脂肪醇和萜烯类挥发性成分在MD中相对含量高于YX5和QL10。甲氧基化合物是MD特征挥发性成分,相对含量为6.43%。芳香醇、酸类和酚类化合物在MD中没有检测到。萜醇和酯类是广东红茶的主体挥发性成分。水杨酸甲酯是酯类中相对含量最高的成分,YX5(14.79%)和QL10(12.04%)中相对含量高于MD(2.43%)。     

百香果全果与果汁发酵酒滋味成分及香气成分对比

目的：提升百香果酒品质。方法：以百香果全果和果汁为原料酿制百香果酒,分别测定其有机酸、氨基酸和挥发性化合物含量,并结合电子舌试验结果评价百香果酒风味成分。结果：2种百香果发酵酒中主要有机酸为酒石酸、柠檬酸、乳酸和苹果酸,但全果酒的前3种有机酸含量均显著高于果汁酒中的（P<0.05）,全果酒和果汁酒中含量最多的有机酸分别为酒石酸（27.20 mg/mL）和柠檬酸（12.49 mg/mL）;除半胱氨酸未检出外,全果酒和果汁酒中16种游离氨基酸总含量分别为88.16,68.88 mg/100 g,且全果酒中4类呈味氨基酸含量高于果汁酒;电子舌测试发现,2种百香果发酵酒中咸味信号强度差异性最大,且全果酒中的鲜味、咸味最强,酸味、涩味和甜味最弱;HS-SPME-GC-MS共检出179种香气成分,全果酒中挥发性风味化合物种类比果汁酒多4种,但其萜烯类物质含量和种类分别比果汁酒的多1,3倍。结论：相比于果汁酒,新型百香果全果酒整体风味（鲜味、咸味、萜烯类物质等）较突出,提升了百香果资源的综合利用度。     

不同风味类型漳平水仙茶的主要品质差异分析

以漳平水仙王子和水仙公主的春茶和秋茶为材料,通过感官审评和生化成分测定,结合多元分析方法探究漳平水仙茶风味品质差异的关键因素。结果表明：漳平水仙王子茶滋味浓醇收敛性强,香气呈甜香带桂花香;水仙公主茶滋味醇爽回甘明显,香气呈清香带兰花香。生化成分分析结果表明,咖啡碱、茶多酚和茶红素可作为鉴别二者不同滋味的特征非挥发物;3-蒈烯、乙酸叶醇酯、正己醇、α-蒎烯、D-柠檬烯可作为鉴别二者不同香型的特征挥发物。本研究将进一步为不同风味漳平水仙茶的分类提供客观、准确的理论依据。