Changes of quality characteristics of Dongchimi by supercritical carbon dioxide as sterilization method

Here we studied the changes on quality characteristics of Dongchimi by supercritical carbon dioxide to manufacture Dongchimi of high quality. There were no distinctive changes of acidity, pH, color difference, free sugar and organic acid of the Dongchimi treated with supercritical CO₂, compared to the control. The content of vitamin C in Dongchimi, which was treated with supercritical CO₂ (at 25 MPa, 35°C) was 0.826 mg/mL, and was similar to that of 0.1 MPa. Unpleasant volatile compounds such as dimethyl disulfide, metyl trisulfide and methyl propyl disulfide in Dongchimi were decreased by supercritical CO₂; also, treatment of supercritical CO₂ was useful to improve flavor of Dongchimi. Polygalacturonase activity was decreased 40.3% after supercritical carbon dioxide treatment at 25 MPa and 55°C.