The problem is familiar to many people who have white or light-colored dogs: You spend hours grooming your buddy to make him show-worthy, but those unsightly brown stains still are discoloring the fur on his muzzle. Such stains are common in many dog breeds, most notably the white breeds. They are caused by trapped saliva that oxidizes in the fur surrounding the mouth. These stains can be annoying for anyone wanting a pristine pooch, but luckily they are easy to eliminate.
Combine in a bowl equal parts lemon juice and table salt. The quantity needed will depend on the size of the stains.
Separate and beat one egg white, and add it to the salt and lemon mixture. Combine thoroughly.
Apply the mixture to brown stains near your dog's mouth. Allow this mixture to completely dry on his fur.
Brush the dried mixture out of your dog's fur. When it's gone, the stain will be as well.