【Source】

 Zhou Hou Bei Ji Fang (A Handbook of Prescriptions for Emergencies)

【Preparation】

 Soak black soybeans in vinegar for 24～48 hours, and cook them fully. Remove dregs and condense the liquid over mild heat to make paste.

【Usage】

 Wash hair and then apply the paste when the hair has dried naturally

【Indications】

 Yellowish-grey withered hair

 Black soybeans