A question about a recipe: Brown Sugar Apple Upside Down Cake with Apple Cider Caramel and Spiced Walnuts

I have a question about the ingredient "baking powder" on the recipe "Brown Sugar Apple Upside Down Cake with Apple Cider Caramel and Spiced Walnuts" from apartmentcooker. how fresh should the baking powder be



Peter November 13, 2012
I wonder if there's some way to store baking powder so that it doesn't "oxidize" -- i.e., isn't stored in contact with air. Maybe a zip-loc with the air pressed out?
Sam1148 November 12, 2012
Try "proofing it" just by putting a 1/2 tsp in a cup water and see if it fizzes.
Also, do that when you first get a fresh unopened can when you open it so you have a baseline visual or amount of fizz it should have.
I usually keep unopened baking powder on hand as a back up. Even with the plastic lid with high humidity etc it starts to degrade faster than the 'use by/exp' date once opened and exposed to air.
Reiney November 12, 2012
There's no question it can go off - I made some scones with some expired baking powder a few weeks ago (I don't bake all that much) and the results were disappointing to say the least :)
Amanda H. November 12, 2012
I like to use baking powder within 12 months. Does the packaging on yours have an expiration date, or do you know how long you've had it for?
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