Had a bread recipe fail? Then learn how to test yeast to see if it is still alive & active. The use of dead or expired yeast can turn your bread into a flat dense brick (instead of a nice fluffy loaf). Active yeast generates carbon dioxide (CO2) bubbles. These bubbles help the dough to rise naturally and your bread to become soft & airy.
You should test your yeast if your homemade bread is having trouble rising, if you haven’t used the yeast for a couple of months, if you are past the expiration date on the yeast bottle/container or if you left the yeast bottle/container open for a few weeks. Checking whether the yeast is good or not will save you from some bread disasters!
Yeast Test Steps
- Fill a measuring cup with 1/2 cup of warm water.
- The water should be around 100 to 110 F (38 to 43 C). FYI – Yeast will not grow if the water is too cold and it will die if the water is too hot. I like to use a digital bread thermometer to quickly measure the temperature of the water.
- Stir 1 teaspoon of white granulated sugar into the warm water.
- Now stir in the yeast
- If you have bread machine yeast or instant yeast, stir in 1 teaspoon of yeast into the water.
- If you have active dry yeast, stir in a full packet of yeast (which is roughly 2 1/4 teaspoons of yeast). See the reasons below on why you should use a full packet.
- Wait 5-10 minutes.
- After a couple of minutes, the yeast should start to bubble. FYI – Instant yeast or bread machine yeast will activate much faster than active dry yeast.
- After 5-10 minutes
- If the yeast is alive & active, you will see a thick layer of yeasty foam in the measuring cup.
- If the yeast is dead or expired, there will be no bubbles and no yeasty smell.
FYI – Unlike bread machine yeast & instant yeast, active dry yeast needs to be activated in liquid before use. Therefore, if the yeast test is successful when using active dry yeast, many people like to use it to make their next bread recipe (rather than throwing the yeast test out). This avoids wasting the now activated yeast. Moreover, many bread recipes that use active dry yeast require a full packet of 2 1/4 teaspoons of yeast (which is the same amount used in the yeast test above).
If you need some new yeast, check out Bread Dad’s bread yeast section for bread machine yeast, instant yeast, active dry yeast, sourdough starters, etc.
Yeast Storage Tips – Extend the life of your yeast!
- After opening, keep the yeast bottle/container tightly sealed. If the bottle/container is not tightly sealed, the yeast will go stale more quickly and/or be negatively affected by moisture found naturally in air.
- If you keep the yeast bottle/container in your kitchen, you should store it somewhere dark and cool. Exposure to light, heat and/or moisture can quickly degrade the shelf life of your yeast.
- For long-term storage, keep the tightly sealed bottle/container stored in your refrigerator or freezer.
- Be aware that once the yeast bottle/container is opened, the approximate yeast shelf life will vary based on the storage method:
- Pantry (room temperature): 1-2 months
- Refrigerator: 4-6 months
- Freezer: 6-12 months
- I recommend testing your yeast more frequently if you are past these shelf life dates. You need to check if the yeast is good past these dates because your yeast may no longer be active.
References
- Wikipedia, Baker’s Yeast
Related Recipes
- Bread Machine Recipes – Complete list of all of Bread Dad’s bread machine recipes.
- Bread Recipes – Bread machine-baked & oven-baked bread recipes.