I buy active dry yeast for baking in 2 lb bags. It takes us about a year to use this much yeast. When I open a new bag, I pour about 4 ounces into a small glass jar (it's actually a really old yeast jar. The expiration date is something like 1998). This is the yeast that I access on a regular basis. I keep it in the refrigerator.
With the rest of the bag of yeast, I fold down the top and secure with a rubber band, then put the opened bag into a gallon ziploc. I keep this yeast in the refrigerator, as well. It still works, even a little over a year later.
I made pizza last night with the tail end of my last bag. It still turned out nicely with a puffy crust.
I have also read that you can store active dry yeast in the freezer, for up to 2 years with success. Just an FYI if you don't go through yeast quickly enough.
Where do you store your yeast?
