Proofing yeast is an important step when baking with yeast. It is done before adding the flour and other ingredients to ensure that the yeast is still active and properly leavens the dough. It only takes a few minutes and it should never be skipped. After all, who wants to go through the trouble and waste of mixing and kneading dough only to find out the dough did not rise because the yeast was stale?
• Check the expiry date on your yeast packet. Because yeast is a live organism, the expiration date is a clear indicator that the yeast is no longer active.
• However, even if the expiry date has not been reached, yeast can turn stale when stored improperly, or when the packet has been left opened. Yeast in an open packet loses 10% of its leavening power every month. Opened packets of yeast should be stored in an airtight container in the fridge.
• Dried active yeast can also be stored in an airtight container in the freezer. The yeast granules do not freeze, but the yeast should be brought to room temperature before using.