沙城产区赤霞珠干红葡萄酒特征香气的研究

沙城产区赤霞珠干红葡萄酒特征香气的研究

STUDY ON IMPACT AROMA COMPOUNDS OF DRY WINES OF CABERNET SAUVIGNON FROM SHACHENG AREA

作者：侯　敏　　导师：李　华

西北农林科技大学　　葡萄与葡萄酒学2011届硕士

摘　要

本试验旨在研究葡萄酒香气物质萃取和沙城产区赤霞珠干红葡萄酒特征香气，用于沙城产区赤霞珠干红葡萄酒特征香气的建立和不同年份沙城赤霞珠干红葡萄酒的区分。本试验以我国沙城产区赤霞珠干红葡萄酒为研究对象，采用化学仪器分析和感官分析研究沙城赤霞珠干红葡萄酒香气。试验共采集了2005年至2009年沙城荣辰庄园赤霞珠干红葡萄酒和2010年采摘的沙城赤霞珠葡萄品种通过小容器发酵酿制而成的干红葡萄酒，完成了沙城产区赤霞珠干红葡萄酒特征香气的研究。

主要研究结果如下：

通过利用超声波辅助、低温无氧的液液萃取葡萄酒香气物质的方法，比较不同萃取溶剂萃取葡萄酒香气物质的效果，确立了葡萄酒香气物质分析前处理方法。萃取溶剂使用二氯甲烷，2-辛醇作为内标物，在冰浴和隔绝氧气的条件下，通过可控温的磁力搅拌器完成搅拌萃取，通过超声波强化液液萃取，浓缩的萃取液供GC-MS上机分析。

使用上述方法分析6个年份的沙城赤霞珠干红葡萄酒，赤霞珠干红葡萄酒共定性定量83种香气物质，其中包括醇类物质25种，酯类物质26种，酸类物质16种，酮类物质9种，醛类物质2种，5种其他的香气物质。不同年份赤霞珠干红葡萄酒香气物质含量和种类存在差异。结果可以看出，随着陈酿时间的延长，虽然存在波动，但醇类物质和酸类物质占全部香气物质的比重呈香总体下降的趋势；除2008年赤霞珠干红葡萄酒，酯类物质所占的比重随着陈酿时间的增长逐步上升；酮类、醛类等其他香气物质也存在不同程度的变化，但变化趋势不是十分显著。根据香气物质的嗅觉阈值计算香气物质的香气活性值，结果显示乙酸异戊酯、己酸乙酯、辛酸乙酯、丁二酸二乙酯、异戊醇、苯乙醇、辛酸、香兰素和5-己基二氢-2(3H)-呋喃酮9种香气物质香气活性值最大，从而对葡萄酒香气质量的贡献最大。

将6个年份的赤霞珠干红葡萄酒含量进行主成分分析，结果显示15种香气物质丁醇、2-丙醇、2-甲基-2丙醇、十四醇、3-壬醇、苯甲醇、辛醇、己酸乙酯、癸酸乙酯、戊酸、己酸、β-大马酮、羟甲香豆素、4-乙基苯酚、香兰素可以覆盖沙城产区赤霞珠干红葡萄酒香气的整体信息。

通过建立沙城赤霞珠干红葡萄酒香气质量评价模型，评价不同年份沙城产区赤霞珠干红葡萄酒香气质量。使用前三个主成分的综合质量评价函数作图，结果发现不同年份的沙城产区赤霞珠干红葡萄酒能够通过质量评价模型被区分开来，说明此方法对于区分不同年份沙城赤霞珠干红葡萄酒有一定的可行性。

采用感官分析和多元统计分析方法确定水果、咖啡、蘑菇、奶油、香草、李子干、(烧)烤味、动物气味、甘草、辛辣和蜂蜜11个描述词可以作为沙城赤霞珠干红葡萄酒的特征香气描述语。

关键词　沙城　赤霞珠　干红葡萄酒　香气　GC-MS和感官分析

Abstract

The target of this experiment is to study how to extract wine aroma and look for impact aroma compounds of Cabernet Sauvignon dry wines from Shacheng. In this experiment,Cabernet Sauvignon dry wines from Shacheng were used as subjects analyzed by chemical instruments and sensory characteristics. Cabernet Sauvignon red wines were separately made from 2005 to 2009 Cabernet Sauvignon grown in Shacheng. In addition,2010 Cabernet Sauvignon red wine was made from ShachengCabernet Sauvignon by using small glass container. Wines of different years were collected as research materials to complete this research about impact aroma compounds of Cabernet Sauvignon dry wines from Shacheng.

The main results are as follows:

Aroma compounds were extracted by ultrasound-assisted LLE in an oxygen-free atmosphere and at low temperature to compare effects of three solvents on analysis of aroma components in Cabernet Sauvignon dry wine by GC-MS analysis in order to establish a method of extracting aroma compounds before GC-MS analysis. 2-octanol was used as internal standard. In an ice water bath and an oxygen-free atmosphere,subjects were extracted with dichloromethane assisted by using magnetic stirrer. And then mixed solution was put in water bath with ultrasound assistance,organic solution is parted from inorganic solution and concentrated to be analyzed by GC-MS.

83a　roma compounds of Cabernet Sauvignon dry wine from 2005 to 2010 were qualified and quantified by the method above,including 25 alcohols,26 esters,16 acids,9 ketones,2 aldehydes and 5 others. Aroma compounds and their contents were obviously different in dry wine of different years. The results showed that percentage of alcohols and acids to all aroma compounds of dry wine fell down with fluctuation from 2010 to 2005;other than 2008 Cabernet Sauvignon dry wine,percentage of esters slowly increased from 2010 to 2005;ketones,aldehydes and others were also different in dry wines of different years,but variation trend was not obvious. According to odor threshold of aroma compounds,their odor active values were calculated by content / threshold. The results showed that OAVs of isopentyl acetate,ethyl hexanoate,ethyl octanoate,ethyl succinate,isopentyl alcohol,2-phenyl-ethanol,ctanoic acid,vanillin and 5-hexyldihydro-2(3H)-Furanone were bigger than other aroma compounds. It was included that 9 aroma compounds were powerful in Cabernet Sauvignon dry winefrom Shacheng.

Quantified aroma compounds were analyzed by principal component analysis. The results showed that n-butanol,2-propanol,2-methyl-2-propanol,tetradecanol,3-nonanol,triphenyl methanol,octanol,ethyl hexanoate,ethyl caprate,n-pentanoic acid,hexanoic acid,β-damascenone,hydroxycoumarin,4-ethyl-phenol,vanillin were considered to be potential to cover whole information about aroma of ShachengCabernet Sauvignondry wine.

Qualification for Cabernet Sauvignon dry winefrom Shacheng was estimated by model of aroma quality established. Quality functions of 3 principal components were referred to draw a PC₁-PC₂-PC₃ scatter plot. The result showed that ShachengCabernet Sauvignondry wines of different years could be distinguished,which successfully proved that designed method was feasible to evaluate Cabernet Sauvignondry wine from Shacheng made in different years.

Through aroma sensory characteristics and multivariate statistical analysis,11 aroma descriptors: fruit,coffee,mushroom,cream,vanilla,dried prune,toasty,animal smell,licorice,spicy and honey were identified as impact description of ShachengCabernet Sauvignon dry wine.

Key words　Shacheng　Cabernet Sauvignon　Red wine　Aroma compounds　GC-MS and sensory analysis