固相微萃取-气质联用法测定湘派豆干老卤挥发性风味物质变化

Determination of Volatile Flavor Compounds in Xiangpai Dried Tofu Brine by Solid-phase Microextraction and Mass Spectrometry

采用顶空固相微萃取结合气质联用技术,对豆干卤汁重复使用过程中挥发性成分进行测定,分析了卤汁不同卤制阶段挥发性物质、种类、相对含量的变化。结果表明:工业化卤汁在161 d内循环使用过程中的挥发性风味物质鉴定出128种挥发性成分,其中醇类44种、酮类5种、醛类15种、酯类13种、烃类27种、酸类8种、芳香族类10种、杂环类5种和含氮类化合物1种;通过主成分分析,确定卤汁中的重要挥发性成分为己醛、芳香醇、茴香脑、壬醛、4-甲基-2-戊酮、1-辛烯-3-醇、辛醛、1-(1,5-二甲基-4-己烯)-4-甲基-苯和月桂烯;卤汁循环使用过程中,随着循环使用时间的增加,卤汁品质趋于稳定,醛类和芳香族类这两类化合物大量产生,并成为卤汁中最主要的挥发性成分,其中以醛类占主要部分,可作为一个评价卤汁风味品质成熟的客观指标。

Headspace solid-phase microextraction(SPME) combined with gas chromatography-mass spectrometry is used to determine the volatile components in dried tofu brine during the process of reuse, and the changes of volatile components, types and relative content in different marinating stages are analyzed. The results show that 128 kinds of volatile flavor components are identified in the industrial brine during 161 days of reuse, including 44 kinds of alcohols, 5 kinds of ketones, 15 kinds of aldehydes, 13 kinds of esters, 27 kinds of hydrocarbons, 8 kinds of acids, 10 kinds of aromatic compounds, 5 kinds of heterocyclic compounds and 1 kind of nitrogen compound. By principal component analysis, the important volatile components in the brine are identified as hexanal, aromatic alcohol, anethole, nonanal, 4-methyl-2-pentanone, 1-octene-3-alcohol, octanal, 1-(1,5-dimethyl-4-hexene)-4-methyl-benzene and laureene. In the process of reuse of brine, with the increase of reusing time,the quality of brine tends to be stable.Two kinds of compounds such as aldehydes and aromatic compounds are produced in a large number and become the main volatile components in the brine.Among them,aldehydes are the main part,which can be used as an objective index to evaluate the quality of brine.