1. Soak black beans in vinegar for three years, and don't eat any more. In this case, black beans will definitely deteriorate, leading to diarrhea and food poisoning after oral administration. Black bean is a common food raw material in clinic.

2. It has the functions of enriching blood, tonifying kidney and blackening hair. Soaking black beans with vinegar is also a common healthy eating method in ordinary people's daily life. It has a good therapeutic effect, and also has a good therapeutic effect on kidney deficiency and premature gray hair.

3. If necessary, it can be treated with black sesame, black wolfberry and Polygonum multiflorum.