Determination and Quantification of 5-Hydroxymethylfurfural in Vinegars and Soy Sauces

Abstract

The organic compound 5-hydroxymethylfurfural (HMF) can be formed from sugars under Maillard reaction and caramelization. In order to study the formation regular of HMF in sugary liquid condiment, vinegar and soy sauce were selected. High-performance liquid chromatography (HPLC) was used to determine the HMF concentrations of various brands of soy sauce and vinegar. The result showed that HMF concentrations were in a range of 0.42 to 115.43 mg/kg for vinegar samples and 0.43 to 5.85 mg/kg for soy sauce samples. The concentrates of HMF were expressed in zero-order kinetics model at 100°C before the maximum HMF generation in all of the tested samples. Longer heating treatment time would reduce the HMF content in tested samples. In addition, HMF content had obviously positive correlation with sugar contents in vinegar samples, but no similar rule was found in soy sauces.