Can Yeast Go Bad?

Love baking? If you love making baked goodies from scratch then you probably worked with yeast. As a baking staple, yeast contains live microorganisms that are activated once it’s been moistened. These microbes generate carbon dioxide, which allows bread to rise before baking. Good quality yeast makes the softest, fluffiest baked goods but spoiled yeast could yield to dense, funky-tasty breads.

Can Yeast Go Bad?

Usually, yeast is sold dry so the risk of contamination and mold growth is reduced. That being said, yeast does not keep forever. It does have a limited shelf life so proper storage is a must. Yeast can keep for a couple of years after the manufacturing date. Still, this is the kind of product that should be used up as soon as possible.

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Dry yeast is made up of beneficial microorganisms that lie dormant. If you store the product for too long, the live microbes will die out eventually. This is the reason why old yeast takes a lot longer to rise than freshly bought yeast. It is also worth noting that opened packs of dry active yeast have a shorter shelf life than unopened packs of dry active yeast.

Signs that Yeast Has Gone Bad

It is easy to tell if your stored yeast has gone bad. Usually, fresh yeast is light beige in color. If the product has turned a weird shade of grey or dark brown, the yeast has gone bad. Check for significant texture changes too. If the yeast started clumping together or if it starts emitting a moldy odor, the product is no longer usable. If the yeast doesn’t activate when moistened, toss the product in the trash.

How to Store Yeast?

Since yeast is made up of live microorganisms, it is quite sensitive to temperature changes, humidity, and air exposure. Unopened packs of yeast should be stored in the pantry, at room temperature. Keep the product away from sources of heat or hot, humid climates. Since yeast activates when moistened, never store this product near the sink.

As for opened packs of yeast, these are best kept in the refrigerator. This goes especially if the product is nearing its expiry date. Refrigeration could delay the degradation of the product, extending its shelf life. While you can use the original packaging of the product, we highly suggest transferring the product to a more resilient container. The container should protect the yeast from fridge moisture.

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When kept in the pantry, dry yeast will keep for 1 to 4 months. When kept in the fridge, the product will keep fresh for 4 to 5 months. Opened packs of yeast will keep in the fridge for 4 months or so. As for cake yeast, this product will keep in the pantry for a week or two.

Can You Freeze Yeast?

Yes, you can freeze regular dry yeast for long-term storage. And no, the live microorganisms won’t die when the product is kept in the freezer. They will only lie dormant until you are ready to start baking.

That being said, cake yeast or compressed yeast has a much shorter shelf life than dry activated yeast because the live microorganisms are much more sensitive to temperature changes. If you’re storing cake yeast, just keep the product in the fridge, never in the freezer. And to be on the safe side, use up your yeast supply as soon as you can.


Stocking up on yeast is a great idea if you love baking! Can yeast go bad? Yeast doesn’t keep forever but as long as the product has been stored properly, you don’t have to worry about the storage life at all. We hope that these tips have been helpful to you!

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