关键词: 辣根精油, 超临界CO2萃取, MIC, 酱油

Abstract: Horseradish essential oil was extracted by supercritical CO2. The effects of extraction pressure, extraction temperature and extraction time on extraction rate of essential oil were investigated. The optimal extraction conditions were optimized by orthogonal tests. The minimal inhibitory concentration (MIC) of horseradish essential oil and its application in soy sauce was determined. The results showed that the optimal extraction process parameters were extraction pressure of 25 MPa, extraction temperature of 40 ℃ and extraction time of 90 min. Under the optimal extraction process, the extraction rate of horseradish essential oil was up to 0.91%. The MIC of horseradish essential oil against Escherichia coli and Bacillus subtilis were 0.04 μL/mL. Compared with 1.0 g/kg sodium benzoate, 0.04 μL/mL horseradish essential oil or 0.02 μL/mL horseradish essential oil coupled with 0.5 g/kg sodium benzoate could remain good quality of soy sauce after 30 days storage at 37 ℃. The simultaneous application of both antioxidants is better than their single applications.

Key words: horseradish essential oil, supercritical CO2 extraction, minimal inhibitory concentration (MIC), soy sauce