Dampen the counter top and sprinkle some good ol' baking soda (sodium bicarbonate) on the stain, just enough to cover it. With a little elbow grease, the stain will vanish.
Source: Baking soda is great for so many things - from being a natural tooth paste, to natural deodorant, and stainless steel sink shiner!
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A paste made with baking soda and water will take Kool-Aid stains out of counters.
Lacquer thinner will easily remove stains from Formica countertops. Be careful not to get it on the wood edge as it will also remove the finish on the edge.
To remove a stain such as food color or fruit stains from a light-colored cabinet top, try putting some dishwasher soap, preferably gel, on a wet cloth and lay it on the stain. The stain should disappear within a few minutes. By Peanut Patty
I used to decorate cakes for fun and always ended up with red food coloring on my counter tops. Then I discovered it could be removed by making a paste of cream of tartar and water.
For wine stains, I just mix a molding plaster and then bleach it to form paste. Apply the paste on the stain and leave for 30 minutes then rinse with water.
This is a page about repairing marks on porcelain countertop. A porcelain finish can get marked and scratched. Removing or covering these blemishes can help it look better.
