At one time just the sound of the name Camille could start people coughing, recalling the tragic Lady of the Camellias, the heroine played by Greta Garbo in the vintage film based on a Dumas story, but that image has faded, replaced by a sleek, chic, highly attractive one.
The expiration date stamped on the baking soda box in the Ochef test kitchen is three years off. We assume that means if you opened the box for the first time 35 months from now, it would still be good.
How to Tell if Baking Powder Has Expired. Baking powder usually has a shelf life of about 9 to 12 months. Testing it is super easy. Just stir about half a teaspoon of baking powder into a cup of hot water. It will immediately start to fizz and release carbon dioxide gas if it's still fresh enough to use.