Why You Shouldn’t Store Flour or Whole Grains in the Pantry

But what about flour and other grains? 

Although you may be inclined to stash your flour and whole grains in a cabinet, it’s not the best place for them. 

The ideal place to store flour and whole grains is in an airtight container or package in the freezer, where it will stay fresher longer. 

This guidance applies to whole grains such as grits, almond flour, oats, quinoa, whole grains of wheat, or whole-grain flour.

Storage instructions on packaging sometimes suggest keeping whole grains and whole-grain flours in a cool, dry place, but to avoid potential rancidity from temperature changes or pests, the best place is the freezer.

Flour and whole grains can go bad quickly in your cabinets because there’s no temperature control. Whole-grain products are rich in unsaturated fatty acids like omega-3s, which are more prone to spoilage. We reached out to our science research editor, Paul Adams, for more information.

“Fatty acids are the building blocks of fat—they can be saturated or unsaturated. Unsaturated fats have fewer hydrogen atoms attached along their carbon atom backbone. The spots without hydrogen are more vulnerable to react with oxygen and turn the fat rancid,” explains Adams. That’s why unsaturated fats are less stable than saturated ones.

The fats in grains are found in the germ, the inner core that contains vitamins and antioxidants. Whole grain means all parts of the grain, including the fats, were ground together to make the finished product. 

An easy way to check to see if your flour or whole grains have expired is with the tried-and-true “sniff test.” If they smell musty or even sour, it’s time to throw them away.