Metabolite Profiling of Fermented Soybean Paste, Prepared by Different Methods

Abstract

In this study, metabolite profiling which applies principle component analysis (PCA) to gas chromatography-mass spectrometry (GC-MS) data sets allowed Doenjang samples according to prepared methods to be discriminated, and volatiles and non-volatile metabolites that contributed to their discrimination were assigned. For the volatiles isolation, a combination of two different techniques, solvent-assisted flavor evaporation (SAFE) and solid-phase microextraction (SPME) were applied, while non-volatiles were extracted and then derivatized prior to GC-MS analysis. The major volatiles, which were related to differentiation of traditional Doenjang samples and commercial ones, were 2-pentylfuran, 4-ethylphenol, dihydro-5-methyl-2(3H)-furanone (γ-valerolactone), butanoic acid, pyrazines, dimethyl disulfide, hexanal, 2- and 3-methylbutanal, esters, 3-hydroxy-2-methyl-4h-pyran-4-one (maltol), ethanol, and 4-vinylphenol, respectively. Also, non-volatiles, such as tyramine, γ-aminobutyric acid (GABA), arabinose, glutamic acid, tyrosine, and aspartic acid were responsible for their differentiation.;본 연구에서는 metabolomics 접근법을 이용하여 한국의 전통발효식품인 된장의 향미관련 성분의 특성을 규명하고 제조방법에 따른 차이를 비교하고자 하였다. 이를 위해 가스 크로마토그래피-질량분석법 (gas chromatography-mass spectrometry)과 다변량 통계기법 (multivariate statistical analysis)을 적용하여 재래식 된장과 개량식 된장의 휘발성 및 비휘발성 대사체들을 프로파일링 (metabolite profiling)하였으며, 그 차이를 비교 분석 하였다. 이에 앞서, 휘발성 대사체는 solvent-assisted flavor evaporation (SAFE) 기법과 solid-phase microextraction (SPME) 기법을 함께 적용하였고, 비휘발성 대사체는 유도체화시켜 분석하였다. 그 결과, 2-pentylfuran, 4-ethylphenol, dihydro-5-methyl-2(3H)-furanone (γ-valerolactone), butanoic acid, pyrazines, dimethyl disulfide, hexanal, 2- and 3-methylbutanal, esters, 3-hydroxy-2-methyl-4h-pyran-4-one (maltol), ethanol, 4-vinylphenol 등의 휘발성 대사체와 tyramine, γ-aminobutyric acid (GABA), arabinose, glutamic acid, tyrosine, aspartic acid 등의 비휘발성 대사체가 재래식 된장과 개량식 된장을 구분하는데 기여하는 화합물로 분석되었다.