Why you should use aluminum free baking power - or make your own: for 1 teaspoon of baking powder, mix 1/2 teaspoon cream of tartar with 1/4 teaspoon of baking soda and 1/4 teaspoon cornstarch. Test the freshness of your baking powder by adding a teaspoonful to a half cup of boiling water. If it boils vigorously, the baking powder is still good but if not then throw it out.
Kitchen Tip: How to Keep Strawberries Fresh…
How to keep strawberries fresh
How to tell if baking powder and baking soda have expired.