How to store cornstarch

How to tell cornstarch has gone bad

General signs for baked goods: baking and cooking, the group USDA lists cornstarch under.

• Small moths, beetles or larvae in the flour or grains
• Clumping or hardening from moisture getting into the bag
• Sharp, crayon-like or paint-like smell from oil
• Baking powder that no longer fizzes when mixed with water
• Chocolate chips with a dull grey bloom or waxy smell

More on baked goods: baking and cooking. The times above are quality guidelines, not safety limits; food that shows these signs goes out regardless of the date.

Storage habits that make the difference

Store flour, sugar and baking powder in airtight containers in a cool, dry cupboard away from the stove. Keep oils away from direct sunlight and heat, and refrigerate nut oils and opened specialty oils to slow rancidity. Label containers with the purchase date so older stock gets used first.