Abstract
A chromatographic procedure was established to fractionate systematically the constituents of rice vinegar, without any loss of its components, into six main fractions, i.e., volatile basic, acidic and neutral fractions and non-volatile basic, acidic and neutral fractions by flush evaporation and ion-exchange resins. 17% of the total nitrogen of rice vinegar was found in the amine fraction and this suggested a possible role of some organic acid-base complexes in the taste of rice vinegar. Using gas chromatography, the amine fraction could not be separated further to its components because of low ionization. But, using thin-layer chromatography, the fraction was separated into nine spots which comprised such components as putrescine, cadaverine, histamine, methylamine, ethylamine, tyramine, phenylethylamine and two unknown compounds. Putrescine and cadaverine were crystallized.
