| ≥1 piece |
A yellowish to pale brownish powder;slight characteristic odour,and taste strongly astringent.Can be soluble in water, alcohol, and acetone, and gives precipitates with most metallic salts,proteins, and alkaloids.A penta-m-digalloyl-glucose having a high molecular weight. Upon hydrolysis with acids or enzymes, it gives gallic acid and glucose.
Gallotannin ( tannic acid ) can used in or acts as: A precipitant f or the extraction of germanium; Slime treatment of petroleum drilling;Metal corrosion-resistance; A stain inhibitor which formulated into paint and coatings to stop the discoloration of a painted wood surface; In tanning animal skins to make leather;Colour fixer, polygenetic dye and fiber deodorizer;The preparations of antibiotics, treating tinea, clearing toxic material and stopping dysentery , and also for synthesizing sulphanilamide synergist;The antioxidant, antiseptic, flavouring agent and flavour adjunct for foods;Clarifying agent for beverages,beer And wines, and decolorant for soy sauce; it also used to the product of bromezyme EC ect.