1, ripening treatment, black plum is sour, which means it is not fully ripe. If this kind of black plum has not softened, it can be ripened. Putting black plum together with apples, bananas and other fruits can play a ripening effect, and it can be ripened in 2~5 days, with sweet taste.

2. Juicing for eating, if the black boll has softened, but the taste is still very sour, this may be because it was picked too early, or it may be a variety problem. This kind of black boll has a poor taste when eaten directly, but when it is juiced and mixed with other sweet foods such as honey or rock sugar, it can improve the taste without affecting the nutritional value.

3. Don't eat undercooked blackberries. Cyanoside is a toxic component of nuts, and it is a kind of glycoside containing cyano group. After eating immature black boll, this kind of glycoside meets water in the mouth, esophagus, stomach and intestine, and releases hydrocyanic acid after enzymatic hydrolysis. Cyanide ions combine with iron-containing cytochrome oxidase, which hinders normal breathing. Due to tissue hypoxia, the body is in a state of suffocation. Hydrocyanic acid can also act on the respiratory center and the vascular movement center, paralyzing them and eventually leading to death.