不同类型发花砖茶特征香气成分研究

采用感官审评方法、固相微萃取/气相色谱-质谱联用技术、香气活性值(odor activity value,OAV)法结合化学计量学方法,分析茯砖茶、发花白茶砖及发花红茶砖特征香气成分。结果表明,从感官上,3种发花砖茶均有典型“菌花香”,但茯砖茶菌花香中带木香,且略带泥土气,发花白茶砖菌花香中带清香,发花红茶砖菌花香中带花香、甜香。3种发花砖茶中共检测出75种挥发性成分,以醛类、醇类、酮类及碳氢化合物为主,其中27种挥发性成分为呈香物质。基于OAV值和偏最小二乘判别分析,鉴定了3种发花砖茶中15种特征香气成分。其中,茯砖茶以具有青气和木香属性的己醛、壬醛、(E,E)-2,4-壬二烯醛、(E,E)-2,4-庚二烯醛、2-正戊基呋喃、3,5-辛二烯-2-酮、甲基庚烯酮、β-紫罗兰酮和氧化芳樟醇Ⅰ为特征香气成分;发花白茶砖以具有清香属性的苯乙醛为特征香气成分;发花红茶砖以具有蘑菇香、泥土气属性的1-辛烯-3-醇,具有花香属性的樟醇、芳樟醇和水杨酸甲酯以及甜木香的雪松醇为特征香气成分。

Characteristic volatile components of different types of fermented brick tea

This research adopted sensory evaluation,solid phase microextraction/gas chromatography-mass spectrometry(GC-MS),odor activity value(OAV)method and chemometrics to analyze the characteristic aroma components of Fu-brick tea,fungal fermentation white brick tea and fungal fermentation black brick tea.The results showed that the three kinds of brick tea had their typical“fungus aroma”,but Fu-brick tea were fungus aroma with woody aroma,slightly muddy,fungal fermentation white brick tea were fungus aroma with medicinal aroma,fungal fermentation black brick tea were fungus aroma with floral aroma.Solid-phase microextraction-gas chromatography-mass spectrometry determined 75 volatile components in three fermentation brick tea samples,among which the main components were aldehydes,alcohols,ketones and hydrocarbons,with 27 kinds of volatile fragrant components.Based on OAV calculation and partial least squares discriminant analysis(OPLS-DA),15 key different aroma components were identified.Moreover,Fu-brick tea had hexanal,nonanal,(E,E)-2,4-nonadienal,(E,E)-2,4-heptadienal,2-n-pentylfuran,3,5-octadien-2-one,methylheptenone,β-ionone and linalool oxide I with green and woody properties as the characteristic aroma component.Furthermore,fungal fermentation white brick tea had phenylacetaldehyde with green properties as the characteristic aroma component.Fungal fermentation black brick tea had 1-octen-3-ol with mushroom fragrance and earthy properties,cinnamyl alcohol,linalool and methyl salicylate with floral properties,cedar alcohol with sweet woody properties as the characteristic aroma component.