Bitter almonds have a small poison, make a fire to remove the skin, frying can remove the small poison, is conducive to the destruction of the bitter almond enzyme, bitter almonds contain bitter amygdalin is bitter almonds contained in the cough and asthma medicinal ingredients. In the process of decoction, there is a period of time when the temperature is suitable for the bitter almond enzyme contained in bitter almonds to play a role, so that the bitter amygdalin is rapidly liberated from the enzyme to release cyanohydric acid and escape. The bitter amygdalin enzyme in the product is destroyed by boiling water in the process of making fire, so the content of bitter amygdalin in the decoction is higher than that in the raw product.

Concocting fire, time on the content of cyanohydrogenic acid also has a great impact on the armed fire fried to the outside black inside brown, cyanohydrogenic acid content decreased by about 44%, fried to the inside and outside of the black, then down to about 10%, with the skin of the bitter almonds and peeled bitter almonds in the same conditions of the decoction, decocted bitter amygdalin difference of nearly double, so the bitter almonds to make a fire to remove the skin is appropriate.