1, the characteristics of oilseed rape itself: oilseed rape belongs to the cruciferous family, containing some bitter compounds, such as sulfide and glucoside, etc.. These compounds will be released in the cooking process, resulting in dishes with a bitter flavor.

2, too long frying time: too long frying time will make the bitter substances in the rape more significantly released, resulting in an increase in the bitter taste of the dishes.

3, improper frying skills: frying vegetables if the fire is too large or use too much oil, will accelerate the release of bitter substances in the dishes, increasing the bitter taste of the dishes.

4, rape is not fresh: rape if not fresh, the leaves will turn yellow, and more likely to have a bitter flavor.