To remove an old coffee stain from a carpet, the following materials are required: white vinegar, a spray bottle, white paper towels, dish washing detergent without lanolin or bleach, a clean brick or rock, hydrogen peroxide, white foam shaving cream and baking soda.
Prepare a paste using baking soda and water. Spread the paste evenly on the coffee stain, and ensure it covers as much surface area as possible. Leave the paste to dry for a few minutes. Use a scrub brush or a vacuum cleaner to remove the paste deposits. The coffee stain should be gone after doing this, leaving the carpet clean and refreshed.
Another way of removing an old coffee stain is by mixing 1 part white vinegar and 2 portions of water and applying it to coffee stain. Allow it to sit for a few minutes, and blot with a clean cloth. If the stain is not removed after this, repeat the process again. Rinse the area with clean water, and wipe with a clean cloth.
Use paper towels to absorb water on the wet area. You may need to apply pressure on the paper towels to ensure they absorb as much water as possible. Old newspapers or books can also be left on the area for a few hours to absorb the water. After all the water is dried up, vacuum the carpet to restore the texture.