Just like all the appliances in your home, a garbage disposal needs regular maintenance. An easy way to clean it and have it smelling fresh is to run cold water into it, turn it on and put in a whole lemon cut in half along with a bunch of ice cubes. Another good cleaning method is to use a tray of frozen vinegar cubes with cold water to run through the system. Do not use chemicals in the garbage disposal, these will damage the system.