Off-flavor of Mustard Paste Part I

Abstract

Pungency of white mustard paste diminished gradually and bitter taste developed during the storage at room temperature. Rate of such off-flavor was greatly affected by temperature, i.e. under 0°C only slight off-flavor and at -20°C no off-flavor developed.
It was confirmed that one of the causes of the off-flavor is the change of p-hydroxybenzylisothiocyanate (pungent principle) to p-hydroxybenzylalcohol (unacceptable taste).
Bitter principle was isolated from mustard paste of off-flavor as a crystalline form. Although the chemical structure was not decided yet, it was found to be a phenolic com pound containing sulfur and nitrogen.