On the Colour of Soy-Sauce

Part 3. On the Substances increasing Colour Intensity of Soy-Sauce

Abstract

The compounds which increase the colour intensity in Soy-sauce were separated as 2, 4-dinitro-phenylhydra zone compounds. Those compounds were characterized (specified) by paper and column chromatography, ultra-violet absorption.
The results are following
1. Carbonyl compounds promote to darkening of Soy-sauce. These carbonyl compounds were composed 13 aldehydes and 4 ketonic acids.
2. In these carbonyl compounds, acetaldehyde was recognized, crotonaldehyde, diacetyl and levulinic acid were presumed, still unknown 10 aldehydes and 3 ketonic acids were gained.