Bitter reasons:
1, if you buy dry lemon slices, soak the water will be bitter because of the dry lemon lemon seeds, remove the lemon seeds, and then soak the water to drink can be avoided bitter flavor.
2, if it is a fresh lemon, boiling water directly bubble will become bitter. And the vitamin C contained in the lemon will also be high temperature bad break. Therefore, it is recommended to use warm water, and is not more than 50 degrees.