If you are using jars to contain your new recipes, preserves, or any food but worry because they have an odor, a squirt of mustard will rid this. Rub 1/2 teaspoon of water and about 1 tablespoon of mustard (a fast-food packet is just the right size!) on the insides of the jar. Let this sit about 2 minutes then rinse. When the mustard mixes with the water, enzymes are created that will neutralize odors.