the lees or “ dregs ” produced during wine making are rich sources of antioxidants . unexpectedly , these materials show significant antibacterial properties as well as antioxidant properties . the lees of red wine which consist of tannins and plant pigments precipitated around crystals of potassium tartarate can advantageously be used directly as a tonic or demulcent . the material can also be used topically for disinfecting the skin , etc . in addition , it is possible to use organic polymers to bind the pigments and / or solubilize them from the tartaric salt to facilitate their use or to make a relatively pure pigment / tannin component .