The main reason that garbage disposals begin to smell is that they catch bits of food and other items that go down the drain. This is perfectly normal, and all you have to do to keep it from becoming a bigger problem for you is to clean your garbage disposal on a regular basis.
If you are up for a pretty intensive cleaning, you can turn your garbage disposal off and take off any removable parts for scrubbing with soap and warm water. It is vital that you make sure your garbage disposal is off and stays off as you do this. This is a great way to take care of a garbage disposal odor, but it will not keep it from coming back.
It is also not necessary to get in there and deep clean your garbage disposal on a regular basis. Instead, you can carry out a few less intensive procedures to help keep your garbage disposal odor free. No matter what cleaning method you use, it is also important to remember to keep your water running any time you turn your garbage disposal on and for about thirty seconds afterwards. This can go a long way towards ensuring that food and other sediment does not build up inside.
One of the reasons that garbage disposals seem difficult to clean is because you cannot use many of the more common household cleaning chemicals on them. Harsher chemicals can damage or erode parts of the garbage disposal, potentially causing larger problems for you later on. Fortunately, there are actually a lot of products that you probably have around your house already that can make cleaning your garbage disposal and getting rid of the unpleasant odor a quick and easy chore.
One good solution is to cut a lemon in half and put it down your garbage disposal along with some baking soda. Once they are down there, turn on the water and then turn on the garbage disposal. Leave it running until you are sure the lemon is gone and you can be confident that the smell will be gone also.