Abstract: The process for extracting gingerol with ethanol aqueous solution under microwave assistance was optimized by evaluating the effects of extraction solvent type, ethanol concentration in water, microwave power, microwave treatment time and material-to-liquid ratio on gingerol extraction using single factor and orthogonal array design methods. The optimum conditions for gingerol extraction were found to be: ethanol concentration, 66%; material-to-liquid ratio, 1:16; microwave treatment time, 70 s; and microwave output power, 300 W. The extraction yield of gingerol was 1.76% under such conditions. Meanwhile, the anti-lipid peroxidation activity of gingerol was assessed and compared with those of two natural antioxidants, and the results revealed that the extract from ginger was able to protect vegetable oils and lard against lipid peroxidation, and that its anti-lipid peroxidation activity was superior to citric acid but inferior to tannic acid.

Key words: gingerol, extraction, microwave, fat and oil, antioxidation