Do you ever notice how the white appliances yellow over time? The yellowing can be caused by many sources ?? nicotine, grease, chemicals, food, and bacteria are all common causes. Now you could just scrub at the yellow filth, for hours. However, not only will you be exhausted, but your appliances could be scratched. There is a much simpler solution to remove those nasty yellow stains. Step 1: Wipe down the surface with a damp cloth or baby wipe. This is to remove all dirt and oils. Step 2: Combine 1/2 cup of bleach, 1/4 cup of baking soda, and 4 cups of warm water in a cleaning bucket or bowl. Mix it well so the baking soda does not just clump together at the bottom. Step 3: Using a clean sponge, wipe the outside of the appliance with the mixture. Pay careful attention to yellow areas and try to avoid areas of trim and non-white surfaces. Allow this to sit for at least 10 minutes. Step 4: Using a clean, damp cloth or baby wipe, wipe away the mixture. Dry with a clean, dry cloth. If any areas have a heavy concentration of yellow, you may need to repeat steps 3 & 4.