Clean and Sharpen
The best solution is a homemade solution of ice, vinegar, and lemons. Buy an ice tray and write “Garbage Disposal” on the bottom. I don’t think anybody would like to have a vinegar ice cube in their drinking water.
Fill the tray with 8 parts water and 1 part vinegar. Then cut up a lemon and drop a small piece of the lemon rind into each slot to help with odor. Leave the solution to freeze.
Remove the tray and drop the ice cubes down into the garbage disposal. Turn on the device and run some water from the faucet to help wash down the bits of debris. Make sure to completely grind up the ice.
The ice works well to not only sharpen the blades but also dislodge any pieces of food that may be stuck. The vinegar will clean off all of the surfaces and the lemon will leave a nice smell.