酵母抽提物中香气活性化合物与前驱物-氨基酸之间关系研究

Analysis between aroma active compounds and precursors-amino acid of yeast extract

酵母抽提物（YE）富含多种滋味化合物,在热处理过程中可作为气味前驱物产生独特的风味特性。利用高压反应釜对YE进行不同温度热处理,温度范围为100~140℃。随后采用固相微萃取（SPME）前处理方法,结合气相色谱-嗅闻-质谱（GC-O-MS）技术,通过香气提取物稀释分析（AEDA）,鉴定关键性气味活性化合物。利用高效液相色谱（HPLC）技术,测定对应的前驱物氨基酸在不同温度下的含量变化。结果表明,YE中对整体风味贡献较大的其中3种关键性气味化合物,分别为呈现可可香、酯香的3-甲基丁醛,煮土豆气味的3-甲硫基丙醛以及甜香的苯乙醛。随着温度升高,3-甲基丁醛的含量呈递增趋势,140℃时达到最大;3-甲硫基丙醛的含量一直增大,140℃达到最大;苯乙醛的含量先增大后减少,130℃含量最高。与此同时,随着温度升高,亮氨酸、甲硫氨酸、苯丙氨酸含量呈现相反的曲线变化。

In the heat treatment process of YE can generate unique flavor characteristic odors,because of rich in taste of compounds as precursors.Using autoclave to heat YE from 100 °C to 140 °C.Using solid phase micro-extraction method,combined with GC-O-MS technique,by aroma extract dilution analysis identified a greater contribution to the key odor active compounds of YE overall flavor.Using HPLC,quantitative changes of corresponding precursor amino acids were studied.The results showed,large contribution to the overall flavor of three kinds of key flavor compounds,presented cocoa aroma/fragrant ester of 3-methylbutanal,boiled potato odor of 3-methylthiopropanal and sweet scented odor of phenylacetaldehyde.As the temperature increases,the content of 3-methylbutanal increased gradually,reaching the maximum at 140 °C;the content of 3-methylthiopropanal also increased,being maximum at 140 °C;the content of phenylacetaldehyde was the maximum at 130 °C,then decreased.At the same time,as the temperature increased,leucine,methionine,phenylalanine showed the opposite curve changes.