Most people who get hooked on baking with yeast eventually buy it in bulk, whether online, from a local coop, a members-only warehouse store or even a friendly bakery if their town is lucky enough to still have a real one and not the typical par-baked and from-a-mix bake shops in supermarkets. Yeast is expensive when purchased in those strips of three sachets — $2.39 at my local market, which works out to $3.19 per ounce — and the small jars most grocers sell aren’t much more economical. However, warehouse stores sell packs of two one-pound bricks for only a buck or two per pound.
But even if you make bread weekly, you might not use both pounds by the use-by date. And that’s okay, as long as you’ve always stored it in the freezer, which preserves it a long time.
I’ll be making bread in the next week or so for the Thanksgiving dressing and needed to know if my yeast is still good. When I packed up to move, I had about 12 ounces of yeast in the chest freezer, vacuum sealed but more than two years out of code. I brought it along anyway, figuring what’s another 12 ounces when I have a few thousand pounds of books. I unpacked it the other day and removed a small amount to proof it, or prove the yeast is still alive and vigorous. That’s it above; you can see it’s fine.
Here’s how to proof yeast: in a cup or small container — I used a little prep cup smaller than a custard cup, which is also fine — mix together about one teaspoon of room-temperature yeast and one teaspoon of sugar, to give the yeast something to eat. Add two tablespoons of water that’s baby-bottle warm and stir it all together. Leave it alone and go do something else for about 15 minutes, by which time it’ll be all foamy and gorgeous if it’s still good. If so, remove a few weeks’ worth of yeast from the brick (if that’s what you have) and store it in an airtight container in the fridge. The rest goes back into the freezer as air tight as you can make it.
Before the advent of instant yeast, which can be mixed as-is with the dry ingredients, active dry yeast was proofed, or proved as some say, during the bread-making process. We don’t have to do that any longer unless we choose to, but proofing’s always a good idea when there are any doubts about yeast’s viability. That’s instant yeast in the photo and it does tend to bubble more in a short time than active dry. Now I know it’s good. I can proceed without adding yet another item to my shopping list.
For more information about instant yeast, please see my earlier post, What Is Instant Yeast? See About Cake Yeast if you’re fortunate to have it. It dies quickly but you can pinch off a bit to proof it. And my Bread category is full of information and recipes, including two recipes for no-knead breads.
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{ 2 comments… read them below or add one }
Could you freeze your proved yeast and bring it back to life? Or only the active dry yeast?
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No, yeast is a living thing and once it’s fully alive with liquid, I think the freezer would kill it, not just render it dormant. I’ve heard anecdotally of people who have frozen starters but I haven’t tried it. It’s such a small amount used when proofing from a brick that I don’t mind tossing it. If it’s a sachet or the full amount of yeast it goes straight into the recipe — if it’s good!