I love to cook. I love my garbage disposal. I do not like the smell that sometimes comes out of my kitchen sink after I have been cooking like a mad man.
Remember those volcano models you made as a kid? That same chemical reaction can be used to freshen your drain. Pour 1/4 to 1/2 box of baking soda down the drain, add 1/2 cup of white vinegar, cover the drain tightly for a few minutes and then flush with cold water. Now, go make yourself a volcano and amuse a child!