Aroma is an important factor to evaluate miso-soup although it is unstable on heating. Volatile components existing in the headspace above miso-soup heated at 100°C were determined by gas-liquid chromatography and the relationship between gas chromatographic data and sensory evaluation was examined.
The following results were obtained :
1. Among volatile components of unheated miso-soup, the following compounds were identified; acetaldehyde, isobutyraldehyde, methyl alcohol, ethyl alcohol and ethyl acetate. In addition, isovaleraldehyde and/or α-methylbutyraldehyde were identified with heated misosoup.
2. During heating, quantities of the aldehydes in the headspace vapor increased, while alcohols and esters decreased.
3. Aroma of miso-soup which was heated in closed container was stronger than that heated in open container.
