HS‐SPME/GC‐MS and chemometrics for volatile composition of Chinese traditional aromatic vinegar in the Zhenjiang region

The main purpose of this study was to determine the volatile composition of Zhenjiang aromatic vinegar, one of the four famous China‐style cereal vinegars, by using headspace solid‐phase microextraction (HS‐SPME)/gas chromatography‐mass spectrum (GC‐MS) and chemometrics. For this purpose, the HS‐SPME sampling method for the volatile compounds of Zhenjiang aromatic vinegar was optimized by a second‐order rotatable central composite experimental design (CCD). A HS extraction of the volatile compounds by incubation on a 65 µm thickness polydimethylsiloxane/divinylbenzene (PDMS/DVB) fibre during 44.2 min at 69.5°C with 1.9 g NaCl add gave the most effective and accurate extraction. By the optimized method, a total of 58 volatile compounds, including 9 alcohols, 13 acids, 16 esters, 5 aldehydes, 4 ketones and 8 heterocycle compounds, were identified from 13 aromatic vinegar samples manufactured in Zhenjiang region. By principal components analysis (PCA), the thirteen vinegar samples were classified into 3 groups, and 10 volatile compounds were chosen as characteristic compounds of Zhenjiang aromatic vinegars. Copyright © 2012 The Institute of Brewing & Distilling     

GC-O-MS法对比3种红枣白兰地的挥发性成分

采用固相微萃取的方法提取3种红枣白兰地中的挥发性成分,以气相色谱-嗅闻-质谱联用对红枣白兰地中的挥发性成分进行分离鉴定。结果测得76种气味活性成分,主要包括酯类、醇类、萜类和芳香化合物。从挥发性成分的数量和总峰面积上看,A#行唐白兰地明显高于B#金相府和C#董家红枣白兰地。气相色谱-嗅闻(GC-O)结果表明,红枣白兰地的主要香气成分是:乙酸乙酯、丁酸乙酯、3-甲基-丁酸乙酯、己酸乙酯、1,1-二乙氧基-2-丙酮、壬酸乙酯、月桂酸甲酯、月桂酸乙酯、苯丙酸乙酯。其中,月桂酸乙酯、苯丙酸乙酯能赋予白兰地红枣的香味,形成此酒的特色。综上所述,从酒的组成和气味评分考虑,A#行唐酒业的香气成分比较全面。     

Effect of Electric Field Treatments on Brandy Aging in Oak Barrels

The influence of applying an electric field (EF) treatment (1 kV/cm, 50 Hz) on a brandy stored in a 5-L oak barrel to simulate the industry application during 180 days was investigated in this paper. The compositions in the EF-treated and control brandy sample including tannins, total phenols, volatile phenols, esters as well as unpleasant compounds were analyzed by high-performance liquid chromatography and solid phase micro-extraction along with gas chromatography–mass spectrometry. Results showed that after being treated by EF the content of most beneficial materials on brandy quality such as tannins, total phenols, volatile phenols as well as esters was increased while the content of some harmful compounds (acetaldehyde, acetal, and higher alcohols) was decreased. The amounts of acetaldehyde and higher alcohols on treated sample were 7.1% and 10.5% lower than the control one, respectively. On the other hand, the content of tannins and total phenols in brandy treated for 180 days was significantly higher than the control sample. Therefore, it was demonstrated that the maturation process and esterification in oak barrel brandy was enhanced and the quality of the brandy was improved by EF treatment. The application of electric field treatment directly on oak barrel is a promising and feasible technology to accelerate brandy maturation.     

白兰地成分检测方法的研究进展

白兰地是世界著名的蒸馏酒之一,以葡萄等水果为原料经破碎榨汁、发酵、蒸馏得到的蒸馏液,再经橡木桶陈酿贮存而成的。酸类、酯类、醛类、醇类等挥发性、非挥发性组分的种类及含量与白兰地的品质有着直接的联系,另外白兰地因产地或蒸馏工艺的差异而含有不同的铜、磷等矿物元素。因此,对白兰地中主要成分的检测方法研究对于确定白兰地质量、鉴定白兰地真伪及市场良性竞争和食品安全均有很重要的意义。本文主要对白兰地中挥发性、非挥发性及矿物质组份含量的分析检测方法研究现状进行了概述,为白兰地的真假鉴别、酒龄和产地甄别、质量分级及风险成分监控等提供可行性的参考。     

不同类型食醋的香气特征及挥发性成分分析

使用超快速气相色谱电子鼻检测市售的香醋、米醋、陈醋3 类共25 个品牌发酵食醋,通过保留指数和外标法对3 类食醋的挥发性化合物进行定性和定量分析,结合气味活性值构建食醋风味轮,比较不同种类食醋挥发性香气差异与化合物含量间关系,并以线性判别分析和随机森林法研究食醋的挥发性化合物差异,进而实现对食醋的区分。从3 类食醋中共检测出44 种挥发性化合物,主要包括醇类、酯类、醛类、酮类、酸类、烷烃类和杂环类。酸类在食醋中含量最高,其次为醇类和醛类,而烷烃类含量最低。食醋样品的气味活性值和气味雷达图说明乙酸、3-甲基丁醛、苯乙醛、5-甲基糠醛、愈创木酚等对香气贡献较大。香醋的酸味、水果香和坚果可可香高于米醋和陈醋。但陈醋的花香高于其他两类。线性判别分析表明,不同品牌和不同种类的食醋均存在明显差异;随机森林通过机器学习对食醋样品的训练和测试,准确度最终达到100%,对不同种类的食醋区分显著,并筛选出3-甲基丁醇、愈创木酚、苯甲醛、丙酮可作为食醋种类鉴别的重要化合物。     

烟台产区三个葡萄品种原白兰地香气成分及感官特征的对比

以烟台产区三种酿酒葡萄白玉霓（Ugni Blanc）、蛇龙珠（Cabernet Gernischt）和赤霞珠（Cabernet Sauvignon）为原料酿造葡萄原白兰地,并对其中挥发性香气成分及其感官特征进行分析。结果表明,三个品种葡萄原白兰地共检测到64种挥发性香气成分;其中白玉霓原白兰地的酯类物质种类最丰富,但含量差异不显著（P＞0.05）;蛇龙珠原白兰地的醇类、酸类、醛酮类及缩醛类物质总含量最高且差异显著（P＜0.05）;赤霞珠原白兰地的芳香类、萜烯类和降异戊二烯类物质总含量最高且差异显著（P＜0.05）;丁酸乙酯等26种化合物可很好实现对三个品种原白兰地的判别分类,蛇龙珠与白玉霓品种间聚类距离更近。三个葡萄品种均符合原白兰地的原料质量要求,感官质量综合排序为白玉霓＞蛇龙珠＞赤霞珠。     

A basis for estimation of consumption: literature values for selected food volatiles. Part III

Quantitative data on volatile compounds have been reported in 16 food items. No publications reporting quantitative data were found for two of these 16 food products, i.e. avocado and jackfruit. About 550 volatile compounds have been assayed globally in the other 14 food products. Mango and raspberry were the products with the greatest number of volatile compounds; the most representative substances were benzaldehyde, ethyl acetate, limonene, and 2-phenylethanol.     

红枣白兰地中特征风味物质的感官组学

采用顶空固相微萃取-气相色谱-质谱联用技术分析鉴定红枣白兰地中的香气成分。首先结合气相色谱-嗅闻技术、时间强度法以及香气萃取物稀释分析初步确定红枣白兰地中的香气成分,然后通过香气活度值（odor activity value,OAV）进一步筛选特征香气成分,最后通过关键香气成分的重组和遗漏/添加实验确定红枣白兰地中的特征香气成分。结果表明：在红枣白兰地中共检测出63?种香气化合物,通过定量分析及OAV分析进一步筛选出21?种重要的香气化合物;21?种香气物质重组实验能够成功模拟红枣白兰地中的香气;香气遗漏/添加实验进一步证实辛酸乙酯为红枣白兰地中的特征香气成分,并且辛酸乙酯、异戊酸乙酯、正丁醇、3-甲基-1-丁醇、戊酸对红枣白兰地中的总体香气具有重要作用。     

Grape brandy production,composition and sensory evaluation

Grape brandy is a spirit drink produced by wine distillation and is matured in wooden casks. According to legislation, it can be characterised by the geographical area where the grapes were produced, the grape variety used and the selected distillation and ageing techniques. Distillation increases ethanol concentration and aromatic constituents which are already present in grapes or are developed during fermentation and distillation. During maturation in wooden casks, compounds that contribute to the aroma and taste are extracted from the wood. Hence the spirit acquires the desired softer mouth feel, aromatic complexity and overall quality. Different methods of analysis are used in order to pursuit this process by analysing volatile and non‐volatile substances and correlate composition with quality. Analysis can also be useful in identification of brandy safety, potential adulterations, provenance and differentiation from other spirits drinks. © 2013 Society of Chemical Industry     

四种不同发酵基质柑橘果醋挥发性成分分析

为了研究四种不同发酵基质柑橘果醋挥发性成分的差异,分别以食用酒精发酵柑橘果醋（EACV）、酒醋连续发酵柑橘果醋（WVCV）、酒汁混合发酵柑橘果醋（WJCV）和酒水混合发酵柑橘果醋（WWCV）四种不同发酵基质的柑橘果醋为研究对象,利用电子鼻和顶空-固相微萃取气质联用技术（HS-SPME-GC-MS）,分析不同发酵基质的柑橘果醋挥发性成分的种类和含量。结果表明,四种柑橘果醋中共检测出138种挥发性成分,包括酯类物质34种、醇类物质37种、酸类物质20种、醛类物质8种、酚酮类物质13种、烃类物质10种和其他类物质16种。挥发性成分总含量高低依次为：WVCV＞WWCV＞WJCV＞EACV,其中EACV保留了更多柑橘果汁的气味,其他三种果醋风味更加浓郁。     

不同酿酒酵母对芒果白兰地香气的影响

为研究不同酿酒酵母（Saccharomyces cerevisiae）对芒果白兰地香气及挥发性物质的影响,以桂七芒果为原料,6种酿酒酵母（M型、P型、A型、R型、E型、C型）为发酵剂制备原芒果白兰地,使用感官品评、气相色谱（GC）法结合主成分分析（PCA）法对其进行分析。结果表明,C型酵母酿造的芒果白兰地香气浓郁且清香、口感清冽,而其他酵母具有异味,口感不协调,酒体粗糙、粗劣等问题。通过气相色谱分析得知,C型酵母产生的酸类物质含量较高,M型酵母产生的醇类、醛酮类物质含量较高,P型酵母产生的酯类物质含量较高,R型酵母产生的芳香类物质含量较高,A型酵母与E型酵母产生的各类挥发性化合物不突出。主成分分析结果表明,C型酵母酿制的白兰地风味物质组成明显区别于其他组,对其影响较大的风味物质主要是乙酸和甲酸乙酯。     

A basis for estimation of consumption: literature values for selected food volatiles. Part I

This paper is a compilation of quantitative data available on volatile compounds reported so far in 18 food items including some legume, cereals, grapes and cheeses as well as crab, lobster, cocoa and chocolate. No publications reporting quantitative data were found for five of these 18 food products, i.e. sultana grape, broad beans, cassava, oat and rye. About 440 volatile compounds have been assayed globally in the other 13 food products and more than 50% of them were found in grape or in grape juice. Levels of these volatile compounds in the selected foods were generally in the ppb range and less often in the low ppm range. Very high levels were found for some carboxylic acids in cheeses and cocoa and for some alcohols and acids as well as for ethyl acetate in grape juice.     

黄芪醋与山西老陈醋挥发性成分分析对比

采用顶空固相微萃取和气相色谱-质谱联用技术,对比分析黄芪醋和山西老陈醋中挥发性香气成分。结果表明,检测并鉴定出黄芪醋和山西老陈醋挥发性香气成分分别为49种和50种,其中酯类14种、酸类13种、杂环类11种、醇类9种、醛类8种、酮类4种、烃类5种、酚类4种和其他类化合物9种,且二者酸类、酯类和杂环类化合物相对含量较高,主要共有成分为乙酸、四甲基吡嗪、苯乙醇、糠醛、3-羟基-2-丁酮等。同时,黄芪醋挥发性成分含量明显高于山西老陈醋,其具有独特的风味品质和营养价值。     

HS-SPME-GC-MS分析红提葡萄白兰地挥发性风味化合物

以新疆产区红提葡萄白兰地为研究对象,采用顶空固相微萃取（HS-SPME）优化其萃取条件,结合气相色谱-质谱（GC-MS）联用技术对其挥发性风味化合物进行定性定量分析,并采用气味活度值（OAV）判断其挥发性成分对白兰地整体香气的贡献度。结果表明,最佳萃取条件为：萃取头二乙烯基苯-羰基-聚二甲基硅氧烷（DVB-CAR-PDMS）50/30 μm,萃取温度40 ℃,萃取时间40 min。在该萃取条件下,共检出62种挥发性化合物,其中酯类、醇类、酸类、醛酮类、缩醛类、萜烯类和其他类物质分别有21种、13种、8种、9种、3种、5种、3种,其相对含量分别为51.19%、6.90%、12.94%、5.76%、3.28%、0.51%和19.42%。通过OAV评价得出具有香气贡献的主要化合物（OAV＞1）共10种,以酯类、醛类和酸类为主。     

两种陈酿期山西老陈醋挥发性成分分析

采用同时蒸馏萃取与GC-MS 联用的方法对两种陈酿期的山西老陈醋挥发性成分进行提取与分析。结果共鉴定出29 种成分,主要是酸、酮、酯、醇、酚和杂环类化合物,这些成分经过相互协调和不断熟化,共同形成山西老陈醋特有的风味,其中乙酸、糠醛、3- 羟基-2- 丁酮、丁二酮和四甲基吡嗪的含量较高,大约占总挥发性成分的90%。两种陈酿期山西老陈醋的挥发性成分有一定的差别,这致使五年和八年陈酿期老陈醋的香气不同。并经过调香实验,确认了对山西老陈醋特征香气起主要作用的香成分。     

气相色谱-离子迁移谱法结合多元统计学分析不同陈酿时间白兰地的挥发性香气成分差异

目的 利用气相色谱-离子迁移谱（gas chromatography-ion mobility spectrometry, GC-IMS）结合化学计量学方法判别不同年份白兰地的差异,建立桶藏白兰地年份酒快速判别预测模型。 方法 基于GC-IMS技术,利用指纹图谱判别各年份白兰地差异和特征性挥发性物质,结合化学计量学方法对各物质吸收峰体积进行数据降维并且建立年份判别模型。 结果 共定性出50种挥发性风味物质,由指纹图谱可判断不同年份白兰地中VOCs含量及种类存在显著差异。利用多元统计方法对鉴定出的香味物质吸收峰数据进行降维分析和可视化操作,主成分分析（principal component analysis, PCA）累计贡献率可达85%,表明不同年份样品具有良好的聚类效果。通过偏最小二乘回归分析（partial least squares-discriminant analysis, PLS-DA）建立年份酒判别模型,得到不同年份酒样的特征性标记物,筛选出22种VIP值大于1的对陈酿白兰地年份判别贡献较大的香气成分。 结论 利用GC-IMS结合多元统计分析可判别年份白兰地中特征性呈味物质种类和含量差异并且建模效果良好,得到研究结果可为白兰地的年份鉴别和质量控制提供经验借鉴和应用思路。     

麦饭石对白兰地中挥发性物质的影响

采用顶空固相微萃取（HS—SPME）和气质联用技术（GC—MS）,对经麦饭石处理和未处理的37％vol白兰地巾挥,发性物质进行分析,并鉴定出102种挥发性物质。结果表明,麦饭石对白兰地中挥发性物质具有影响作用,如丰要的杂醇油（异戊醇、4-甲基-2-戊醇、4-甲基-1-戊醇）及酯类（辛酸乙酯、癸酸乙酯）的相对含最有所降低,而萜烯l炎、醛类物质的相对含量增加,改善了白兰地香气的质量。     

异常汉逊酵母与酿酒酵母混菌发酵对苹果白兰地风味物质的影响

比较不同菌种发酵的苹果白兰地中风味物质种类及其含量的差异,采用液液萃取和气相色谱-质谱联用技术对5种不同接种方式发酵的苹果白兰地中风味物质进行测定,并就风味物质和不同发酵方式分别进行对应分析和聚类分析。结果表明:不同接种方式发酵的苹果白兰地共检测到69种香气成分,其中,酯类19种,醇类31种,酸类10种,醛酮类3种,酚类4种,烯烃类2种;而顺序混合发酵Ⅰ(先接种异常汉逊酵母24 h后接种酿酒酵母)在异常汉逊酵母与酿酒酵母的协同作用下有效促进了更多酯类、醇类物质的合成,降低了脂肪酸的含量,增加了香气成分的种类,发酵的苹果白兰地风味物质最复杂,改善了苹果白兰地的品质及风味。     

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.     

双菌协同发酵苹果醋研究及其品质分析

以苹果为原材料，利用巴氏醋杆菌（Acetobacter pasteurianus）和植物乳杆菌（Lactobacillus plantarum）进行双菌协同发酵生产苹果醋。采用单因素和响应面试验优化发酵工艺条件，并与巴氏醋杆菌发酵苹果醋的主要理化指标及风味物质进行对比。结果表明，双菌协同发酵苹果醋最佳工艺条件为初始酒精度9%vol、发酵温度31 ℃、巴氏醋杆菌与植物乳杆菌接种量均为10%（V/V）、转速170 r/min，发酵时间12 d。此优化发酵工艺条件下，苹果醋总酸为56.13 g/L。与单菌发酵苹果醋相比，双菌协同发酵苹果醋总多酚、总黄酮、维生素C、游离氨基酸质量浓度显著增多（P＜0.05），抗氧化性明显增强。在单菌和双菌协同发酵苹果醋中分别检测到25种和36种挥发性化合物，双菌协同发酵苹果醋具有更多的酮类和酯类化合物，表现出更好的风味。