用热脱附方法分析哈密瓜香气成分

为探究哈密瓜主要香气成分,该文采用热脱附方法对哈密瓜果肉、哈密瓜果汁的香气进行富集,经气相色谱质谱法(GC-MSD)联机进行检索分析.结果显示,哈密瓜果肉、哈密瓜果汁香气成分和含量存在一定的差异,并从中检测出56种香气成分,其中哈密瓜肉香气成分有31种,哈密瓜汁的香气成分有46种,共同香气物质为乙酸甲酯、乙酸乙酯、丙酸...     

不同萃取方法对山楂汁香气成分测定的影响

为研究不同的萃取方法对山楂汁香气成分测定的影响,采用顶空固相微萃取（HS-SPME）和液液萃取（LLX）对山楂汁中的香气成分进行富集,并结合气相色谱-质谱联用（GC-MS）对其进行定性和半定量分析。结果表明,HSSPME共检测出21种香气成分,主要是顺-3-己烯醇、α-萜品醇、顺-乙酸-3-己烯酯、顺-丁酸-3-己烯酯、苯甲醇和甲酸己酯等,其含量分别为79.4、68.1、60.4、60.1、49.9、33.2μg/L;LLX共检测出20种香气成分,主要是顺-3-己烯醇、顺-乙酸-3-己烯酯、顺-丁酸-3-己烯酯、丁子香酚、丙酮酸乙酯和柠檬酸,其含量分别67.9、63.4、57.4、51.4、34.5、30.3μg/L。通过比较分析可知,不同的方法因工作原理不同,得到的香气成分不同且含量差异较大。      

不同品种甜瓜的关键香气成分鉴定及感官特性形成分析

该研究首先利用气相色谱-质谱-嗅闻技术（Gas Chromatography-Mass Spectrometry-Olfactometry,GC-MS-O）结合香气活力值（Odor Activity Value,OAV）从伽师瓜、黄河蜜瓜、西州密25号和西州密17号中分别鉴定出9、16、12和10种关键香气物质,其中的乙酸乙酯、乙酸丁酯和乙酸苄酯等7种香气物质是我国厚皮甜瓜主要的特征香气成分;采用定量描述分析确定了甜瓜的果香、瓜香、甜香、青香、花香和麝香-烘烤香6个感官特性并给出了相应的感官得分;利用聚类热图法分析了4种甜瓜中关键香气物质种类和含量的差异性;偏最小二乘回归法（Partial Least Squares Regression,PLSR）分析了甜瓜香气感官特性形成的原因。结果表明乙酸乙酯与甜瓜麝香-烘烤香感官属性形成相关;2-甲基丁基乙酸酯和乙酸丁酯与甜瓜果香感官属性形成相关;乙酸苄酯、异戊醛、(E,Z)-3,6-壬二烯-1-醇、硫代乙酸甲酯、(Z)-6-壬烯-1-醇和3-甲基丁酸乙酯与甜瓜的花香和瓜香感官属性形成呈显著相关性。该研究为我国厚皮甜瓜风味香气的改良以及其感官质...     

5个番石榴品种在南宁地区的引种试种初报

为了分析3种红肉番石榴绿熟期和黄熟期的挥发性成分差异,采用气相离子迁移谱（Gas chromatography-Ion mobility spectrometry,GC-IMS）检测3种红肉番石榴绿熟期和黄熟期的挥发性成分。结果表明,3种红肉番石榴绿熟期和黄熟期分别检测出121种和133种挥发性成分,主要是酯类、醛类、醇类和酮类化合物。3种红肉番石榴的主要香气物质包括己醛（单体和二聚体）、2-己烯醛、反式-2-丁烯酸乙酯、乙酸乙酯（二聚体）、（Z）-3-己烯-1-醇（二聚体）、1-戊烯-3-酮（二聚体）和反式-2-戊烯醛（二聚体）。萜烯类化合物如β-罗勒烯、γ-松油烯、1,8-桉叶素等也是3种红肉番石榴的重要挥发性成分。3种红肉番石榴的挥发性成分差异较大,尤其是‘西瓜红’与另外2种番石榴的差异最大。顺-3-己烯基乙酸酯(二聚体)、乙酸丙酯(二聚体)、2-甲基-2-丙醇、苄醇、辛醛（二聚体）等是‘西瓜红’的特征挥发性成分。对44种主要挥发性成分的峰体积进行分析,γ-松油烯、1,8-桉叶素（单体）、反式-2-戊烯醛（二聚体）、1-戊烯-3-酮（二聚体）、乙酸乙酯（二聚体）等多数挥发性成分的含量在3种番石榴果实后熟过程中大幅增加,而β-罗勒烯（单体）、甲基庚烯酮等少数挥发性成分的含量大幅减少。

     

古井贡酒酒醅挥发性香气成分的GC-MS与GC-O分析

应用溶剂辅助风味蒸发法结合气相色谱-质谱联用技术、气相色谱-嗅闻技术对古井贡酒酒醅中的挥发性香气成分进行分析。经计算保留指数并结合标准品比对,共定性出148 种挥发性香气成分,其中有21 种香气强度较高的化合物。应用内标法并结合相关阈值对这21 种嗅闻强度高、持续时间长的重要风味组分进行定量分析及香气活度值（odor activity value,OAV）分析,比较它们对酒醅整体香气的贡献程度,其中香气贡献度最高的4 种物质分别为己酸乙酯（OAV=2 817）、辛酸乙酯（OAV=534）、丁酸乙酯（OAV=519）、乙酸-3-甲基丁酯（OAV=137）,酒醅中其他较重要的香气化合物为癸酸乙酯、丁酸、乳酸乙酯、苯乙酸乙酯、苯丙酸乙酯、乙酸苯乙酯、己酸、2,3-丁二醇、乙酸、丙酸和苯乙醇。     

米酒生香酵母的分离筛选鉴定及其性能研究

为获得米酒酿造中优良的生香酵母,通过嗅闻法初筛得到6株香气突出的菌株,通过测定菌株发酵米酒过程中乙酸乙酯、β-苯乙醇、乳酸乙酯和乙醇的积累量,复筛获得菌株11Z1,其积累量分别为(2.883±0.260)、(0.301±0.028)、(0.080±0.008)和(37.296±1.036)g/L。经形态学及分子生物学方法鉴定菌株11Z1为Cyberlindnera fabianii;对其发酵液进行风味物质分析,检测出主要风味物质共21种,包括醇类5种、酯类3种、酸类5种、酚类1种、酮类1种、烷烃类2种和其他类4种,这些风味物质对增加酒的香气及形成酒体风格具有积极作用。此外,分别在培养基中添加风味前体物乙酸、L-苯丙氨酸和L-乳酸,进一步探究其对菌株11Z1酿造米酒风味物质形成的影响,结果表明,添加体积分数0.3%乙酸发酵9 d、8 g/L L-苯丙氨酸发酵4 d、体积分数0.4%L-乳酸发酵8 d,乙酸乙酯、β-苯乙醇及乳酸乙酯积累量分别达到最大,与未添加前体物相比分别提高了160.71%、215.48%和144.04%。综上,菌株11Z1具有突出的生香能力,展现出在米酒酿造中巨大的应用潜力。     

Volatile profile of Spanish-style green table olives prepared from different cultivars grown at different locations

The volatile profiles of Spanish-style green table olives elaborated with Manzanilla, Gordal and Hojiblanca cultivars grown at different locations in Spain were established by solid phase micro-extraction (SPME) and gas chromatography coupled to mass spectrometry (GC–MS). A total of 102 volatile compounds were identified, belonging to distinct chemical classes, and 20 of them are reported for the first time in table olives. The headspace profile was predominated by alcohols and phenols, followed by acids and esters, whereas the relative amounts of the remaining classes were quite lower (< 5% in general). The principal compounds characterizing the headspace for most samples were p-creosol, phenylethyl alcohol, acetic acid, ethanol, benzyl alcohol, ethyl acetate, and (Z)-3-hexen-1-ol. Significant differences in the proportions of volatile compounds between samples from the Gordal cultivar and those from Manzanilla and Hojiblanca cultivars were detected and statistically visualized by principal component analysis (PCA). Among all the identified compounds, only (E)-2-decenal showed significant differences between the three cultivars without being significantly affected by locations where the fruits were grown.     

花椒酒固态发酵工艺研究

以柠檬烯含量、芳樟醇含量和感官评分为指标,对花椒酒的固态发酵工艺进行研究,采用正交实验优化了工艺条件,并利用气相色谱-质谱法（GC-MS）进一步对花椒酒的风味成分进行分析鉴定。结果表明:红花椒适于花椒酒酿制,最佳酿造工艺条件为花椒用量0.4%、花椒粉碎度60目、酿造时间9 d,所得花椒酒中柠檬烯和芳樟醇分别为45.4 mg/L和39.8 mg/L,感官评分90分。柠檬烯、芳樟醇、月桂烯、乙酸芳樟酯、（-）-4-萜品醇、桉叶油醇、α-松油醇等与乙醇、正丙醇、叔丁醇、乙酸乙酯、异丁醇、异戊醇、乙缩醛等共同构成了花椒酒的典型风味。      

基于AEDA和OAV值确定西瓜汁香气活性化合物的比较

本研究采用溶剂辅助风味蒸发提取西瓜汁的香气成分,利用气相色谱-质谱联用结合嗅闻仪定性定量分析其香气活性化合物,共鉴定出49种化合物,主要是小分子的酮、醛、硫醚等物质,酯类物质中只检测到一种物质,即乙酸乙酯,且浓度较低。本研究首次检测到醚类物质。OAV计算和AEDA两种方法共同鉴定出11中物质,顺,顺-3,6-壬二烯醛、顺-3-壬烯-1-醇、反,顺-3,6-壬烯-1-醇、反-2-壬烯醛、壬醛、1-壬醇、2-戊基呋喃、己醛、辛醛、顺-6-壬烯醛、反-2-辛烯醛。其中有五种香气活性物质,即顺,顺-3,6-壬二烯醛、顺-3-壬烯-1-醇、顺-6-壬烯醛、顺-2-壬烯醛、反,顺-3,6-壬烯-1-醇都能被实验员嗅闻到,且具有较高的OAV值。这表明,AEDA和OAV计算在西瓜汁香气活性化合物分析上具有一定的相似性。     

四种香气物质在MCM-41分子筛上的脱附活化能

本文研究了苯乙醇、大马酮、乙基香兰素和乙酸乙酯香气物质在存储材料MCM-41分子筛上的吸附结合力。采用程序升温脱附(TPD)实验测定了这四种香气物质分子在MCM-41上的程序升温脱附曲线,估算了它们的脱附活化能。同时还采用从头计算(abinition)法分别计算了它们的电负性。研究结果表明:苯乙醇、大马酮、乙基香兰素和乙酸乙酯在MCM-41上的脱附活化能分别为86.16、71.13、55.47和46.09 kJ/mol。苯乙醇、大马酮、乙基香兰素和乙酸乙酯的电负性分别为2.386、2.664、3.064和3.521。按照Pearson碱类物质软硬划分标准,苯乙醇和大马酮均属于软碱物质,乙基香兰素和乙酸乙酯均属于硬碱物质。苯乙醇和大马酮在MCM-41上吸附结合力要明显强于乙基香兰素和乙酸乙酯在MCM-41上的吸附结合力,根据软硬酸碱理论(HSAB),可以推定MCM-41的表面具有软酸的性质。     

Characterization of odor-active compounds in Croatian Rhine Riesling wine, subregion Zagorje

The aroma of Rhine Riesling must and wine was studied to determine the most intense odor-active compounds. The study was carried out using a special designed method of gas chromatography-olfactometry (GCO) to detect characteristic odorants, which were identified by GC-MS. Generally, the obtained results showed higher odor intensities for the wine than for the must samples. The aroma substances 2-phenylethanol, 3-methyl-1-butanol, 3-(methylthio)-1-propanol, ethyl propanoate, ethyl butanoate, ethyl 3-methylbutanoate, 3-methyl-1-butanol acetate, ethyl hexanoate, ethyl octanoate, ethyl 3-hydroxybutanoate, 2-phenylethyl acetate, hexanoic acid, 3-methylbutanoic acid, butanoic acid, β-damascenone, γ-undecalactone and 4-vinylguaiacol were detected as the most active odorants in the Rhine Riesling wine. The aroma of Rhine Riesling must was characterized by 2-ethyl-1-hexanol, (E)-2-penten-1-ol, 1-terpinen-4-ol, benzyl alcohol, 2-phenylethanol, α-terpineol, d-limonene, β-damascenone, 3-methylbutanoic acid and benzeneacetaldehyde.     

SDE-GC-MS 分析乌梅中挥发性成分

为分析乌梅中挥发性成分的组成,采用同时蒸馏萃取(simultaneous distillation extraction,SDE)提取,气相色谱-质谱联用(gas chromatography-mass spectrometry,GC-MS)对乌梅中挥发性成分进行分析。从乌梅提取物中共鉴定出47种成分,主要包括酚类12种、酸类10种、酯类7种、杂环化合物6种、酮类4种、醛类4种和醇类2种等,其中糠醛(44.09%)、乙醇(12.71%)、苯甲醛(11.31%)、乙酸(7.33%)、十六酸(6.65%)、5-甲基糠醛(3.34%)、苯甲醇(2.04%)、乙酸乙酯(1.41%)和丁香酚(1.11%)。通过4次平行GC-MS分析,验证了定性定量结果的可靠性。     

First study of determination of aromatic compounds of red wine from Vitis vinifera cv. Castañal grown in Galicia (NW Spain)

Wines produced from Vitis vinifera cv. Castañal from Galicia (NW Spain), harvest 2002 and 2003, were submitted to gas chromatography (GC/FID). A total of 36 varietal and fermentative aroma compounds were identified and quantified. The total concentration of aroma compounds in 2002 and 2003 vintage was 872.06 and 520.70 mg/L, respectively, which include free and bound terpenes and C₁₃-norisoprenoids, alcohols, acetates and ethyl esters. To estimate the contribution of specific compound to the aroma, the odour activity value (OAV) was calculated using the concentration of each component and the corresponding odour threshold reported in the literature. From 36 compounds identified, 10 were determined as the most powerful odorants: β-ionone, 3-methyl-1-butanol, benzyl alcohol, 2-phenylethanol, ethyl acetate, isoamyl acetate, ethyl lactate, ethyl butyrate, ethyl hexanoate and ethyl octanoate. These data suggested Castañal wines as a fruity (blackberry) and floral (rose) product.     

1‐Methylcyclopropene effects on temporal changes of aroma volatiles and phytochemicals of fresh‐cut cantaloupe

BACKGROUND: Orange‐fleshed cantaloupe melons have intense aroma and flavor but are very perishable during storage life. Fresh‐cut processing enhances ethylene‐mediated quality losses. Post‐cutting 1‐methylcyclopene (1‐MCP) application to fresh‐cut cantaloupe was evaluated for its effects on quality attributes, phytochemical content and aroma volatiles. RESULTS: Fresh‐cut cantaloupe (Cucumis melo var. cantalupensis ‘Fiesta’) cubes treated with 1.0 µL L^?1 of 1‐MCP for 24 h at 5 °C, packaged in vented plastic clamshells and stored under normal atmosphere at 5 °C for 9 days, preserved their soluble solids, total phenolics, total carotenoids and β‐carotene contents, but significant softening occurred. A significant increase of non‐acetate esters and a decrease of aldehydes occurred during storage. Most quality attributes of fresh‐cut cantaloupe were unaffected by the treatment with 1‐MCP. 1‐MCP‐treated fresh‐cut cantaloupe accumulated higher levels of propyl acetate, 2‐methylbutyl acetate, methyl butanoate, methyl 2‐methyl butanoate, methyl hexanoate, 2‐methylbutyl alcohol and phenethyl alcohol, and lower levels of benzyl alcohol and heptanal than untreated controls. CONCLUSION: Post‐cutting treatment with 1‐MCP affected nine of the flavor‐important volatiles, particularly those derived from the amino acids isoleucine and phenylalanine, but had no practical effect on phytochemicals or other quality attributes. © 2012 Society of Chemical Industry     

The effect of air-drying on glycosidically bound volatiles from seasonally collected origano (Origanum vulgare ssp. hirtum) from Croatia

The glycosidically bound volatiles were isolated from fresh and airdried origano by exhaustive percolation with ethyl acetate. After the purification of glycosidic fraction, the enzymatic hydrolysis with beta-glucosidase was performed. The obtained aglycones were analysed by GC-MS. Eighteen compounds were identified. The seasonal variations of main aglycone contents from the fresh plant material were: thymoquinone (3.10-6.18 mg/kg), benzyl alcohol (1.33-3.62 mg/kg), 3,5,5-trimethyl-4-(3-hydroxy-1-buthenyl)-2-cyclohexen-1-on (0.51-3.35 mg/kg), 2-phenyl ethanol (0.42-2.98 mg/kg), eugenol (0.93-2.55 mg/kg), thymol (0.70-1.40 mg/kg) and carvacrol (0.88-1.40 mg/kg). The season of collecting influenced the content and composition of the glycosidically bound volatiles of origano. Air-drying effected mostly the yield of these compounds.     

Production of volatile compounds by Muskmelon,Cucumis melo

The volatile constituents of ‘PMR 45’, ‘Top Mark’, ‘Honeydew’ and ‘Crenshaw’ cultivars of Muskmelon were examined by trapping the essence on Porapak Q and analysing the eluted compounds on wall coated open-tubular glass capillary columns. The relative concentrations of forty-three compounds were determined. Also, by direct sampling of gas from the fruit cavity of ‘PMR 45’ and ‘Top Mark’ cantaloupe cultivars, the relative concentrations of fifteen compounds were measured daily over a period of eight days. Computer-constructed arrays of chromatograms revealed trends in the progressive changes of volatile compounds produced by the ripening fruits. The volatile constituents measured in this study could be fitted into groups, depending on the pattern exhibited by the production of that compound. One group showed a continuously accelerating rate of production (e.g. ethyl esters, acetaldehyde, ethanol) and another increased rapidly and then plateaued (e.g. acetate esters).     

Metabolite production of yeasts on a strawberry-agar during storage at 7 degrees C in air and low oxygen atmosphere

Changes of different quality factors of strawberries have been described until now from a physiological point of view. Possible effects on quality caused by yeast proliferation have not been described. To elucidate the metabolic activity of yeasts (i.e. Debaryomyces melissophilus, Rhodotorula glutinis, Cryptococcus laurentii), isolated from strawberries, they were inoculated on a simulation medium of strawberries (strawberry-agar). Their activity was measured by analysing and correlating microbiological counts, metabolite concentration in the headspace as well as in the medium, and sugar consumption. The isolated yeasts from strawberries could grow on the strawberry-agar, both under air conditions and modified atmosphere (MA) conditions. The maximum count for the yeasts reached 7.5-8.5 log cfu cm(-2) (air conditions) and 5.6-6.4 log cfu cm(-2) (MA conditions). Production or consumption of a number of compounds could be detected when microbial counts reached levels between 4.7 log cfu cm(-2) and 8.5 log cfu cm(-2) depending on species and atmospheric conditions. A range of volatile organic compounds, produced by the yeasts, was detected: acetone, ethyl acetate, ethanol, isopropyl acetate, ethyl butyrate, 1-propanol, 2-methyl-1-propanol, 1-butanol, 2-methyl-1-butanol, 3-methyl-1-butanol, 1-hexanol and hexyl acetate. These compounds are able to influence the sensory properties of strawberries. A simultaneous decrease in sugar concentrations (sucrose, glucose, fructose) was observed. When ethanol reached high concentrations, ethyl acetate and ethyl butyrate were produced. This production can be attributed to a detoxification of ethanol by yeasts. The fermentative metabolism of yeasts during aerobic conditions could be explained by the Crabtree effect. As the detected volatile organic compounds produced by yeasts are also found in fresh strawberries, it can be concluded that these compounds are produced both by microbiological and physiological processes.     

Volatile composition of Mencı́a wines

Monovarietal Mencı́a wines from two different Appellation of Origin Controlled (AOC) of Galicia (NW Spain) were analyzed. The content of some varietal and fermentative volatile compounds was determined by gas-chromatography and GC–mass spectrometry. These red wines, independently of their origin, showed terpene profiles, that were typical of their varietal characteristics with an important contribution of linalool, citronellol, α-pinene and β-pinene. Other important varietal compounds were: norisoprenoids (α- and β-ionone, and theaspirane), phenyl-ethanol and benzyl alcohol. The 67 analytical variables were submitted to analysis of variance, and the results showed that only nine volatile compounds were significantly different (p<0.05) among the two AOC (trans-3-hexenol, 1-butanol, isobutanol, ethyl acetate, hexyl acetate, butyric acid, γ-butyrolactone, methionol, and N-(2-hydroxy-ethyl)-acetamide). Principal component analysis showed the differentiation of wines according to geographical areas.     

Characterisation of odour‐active compounds in papaya (Carica papaya L.) wine

The volatile compounds of papaya wine were isolated by continuous solvent extraction and analysed by gas chromatography‐flame ionization detector and gas chromatography‐mass spectrometry. A total of 118 volatile constituents were detected, and ninety‐seven were positively identified. The composition of papaya wine included fifty‐three esters, twenty‐two alcohols, nine acids, seven phenols and derivatives, seven sulphur compounds, five lactones, five terpenes, three ketones, two aldehydes and five miscellaneous compounds. The aroma‐active areas in the gas chromatogram were screened by application of the aroma extract dilution analysis and by odour activity values. Six odorants were considered as odour‐active volatiles: ethyl octanoate, (E)‐β‐damascenone, 3‐methylbutyl acetate, benzyl isohtiocyanate; ethyl hexanoate and ethyl butanoate.     

香气活度值法结合PLSR用于梨酒特征香气物质筛选与鉴定

采用固相微萃取-气相色谱-质谱对市售3种梨酒香气物质进行分离鉴定,共检出43种挥发性成分,其中醇类16种、酯类15种、醛类4种、酮类2种、酚类1种、酸类3种和其他化合物2种。结合香气活度值(odor activity value,OAV)和偏最小二乘回归(partial least squares regression,PLSR)确定梨酒特征香气物质并推断其对梨酒香气的贡献程度。OAV结果表明:梨酒特征香气物质主要为异丁醇、1-辛醇、1-壬醇、苯乙醇、丁酸乙酯、3-甲基丁酸乙酯、乙酸异戊酯、己酸乙酯、辛酸乙酯、β-大马士酮、丁香酚。建立6个感官属性(发酵香、酸香、果香、花香、甜香、清香)与43种香气物质的PLSR模型表明,苯甲醇、正丁醇、丁二酸二乙酯的OAV小于1,但对梨酒的香气有贡献,经OAV确定的梨酒特征香气物质与发酵香和甜香属性具有很好的相关性,而在清香、酸香、果香和花香上的相关性不明显。