Purpose: Brewing Tannin is a high-purity tannic acid extracted from gallnuts using a purely physical method. It is suitable for various stages of beer brewing, including fermentation, post-storage, and before filtration. It selectively adsorbs high-molecular alkaline, sulfhydryl-containing, and hydrophobic sensitive proteins in beer, reduces aldehyde substances in beer, and enhances the beer's antioxidant capacity. It improves the non-biological stability and flavor stability of beer. Usage: It must be prepared into a 5-10% tannin solution using deoxygenated brewing water or distilled water before use. The diluted tannin solution is added via a metering pump into the beer pipeline before the wort enters the fermentation tank; or into the temporary storage tank after fermentation is completed; or into the beer pipeline before final filtration, prior to entering the buffer tank. Recommended dosage: 10-30 ppm; the dosage varies depending on the addition point. Preparation method: Use a stainless steel or plastic container, inject deoxygenated water or distilled water at room temperature, and stir rapidly. When a vortex forms, slowly pour the mashing tannin into the container while stirring continuously to ensure complete dissolution into a 20-25% solution. Dilute to a 5-10% solution before use. Avoid contact with oxygen as much as possible. Avoid using iron, aluminum, or other metal containers and tools.