Learn the basics of how to use  yeast so you are confident in baking with yeast for any recipe! In baking with yeast 101 you will learn the basics of what yeast is, what makes it grow, what puts it to sleep, and how to avoid killing your yeast! 

Loaf of yeast bread

When I ask my readers what thing intimidates them the most about baking, they often tell me that it is yeast. I believe that arming ourselves with knowledge helps things feel much more approachable in the kitchen. So let’s talk all about yeast, the different types of yeast, and how we can insure that we will be successful in baking with yeast. 

What is Yeast?

Let’s start first with the simple definition of what yeast is. Yeast is a fungus. Yep, you heard me correctly. Yeast is alive, it is a fungus, and it happens to be everywhere.

Yeast is floating through the air, living in our bodies, on our skin, in the dirt, and is naturally occurring in many foods that we eat. But the yeast that we are talking about here is the kind of yeast used in baking. 

Kinds of Yeast for Baking

There are 3 main forms of yeast that bakers use to make their baked goods rise: Natural yeast, fresh yeast, and dry yeast. For baker’s just starting out working with yeast, dry yeast is usually the starting place and where most of this article is going to focus. However, let’s review the basics of all forms so we have a total understanding of baking with yeast.

Natural Yeast / Wild Yeast Starter

As stated, yeast is everywhere. It is floating in the air, it is living on our skin and in our bodies, and is in the grains we eat. A natural yeast starter (aka wild yeast starter or sourdough starter) is a culture of natural yeast cells and good bacteria that is used instead of dry or fresh yeast to leaven bread. 

To create a sourdough starter, flour and water are mixed together and left out to ferment. The flour and the air contains natural yeast cells and good bacteria. When the flour is hydrated, it will start fermenting. You can see my sourdough starter, loving named “Millie”, pictured. 

In order to cultivate a lively community, each day some of the mixture is thrown out and more fresh water and flour is added to the portion that is kept. This is called a “feeding” and it provides more food for the current community of yeast and bacteria, as well as introduces more yeast and bacteria into the mixture.  

The topic of creating a yeast starter, maintaining it, and baking with it is a huge topic that I will delve into on another day. 

Fresh Cake Yeast

Cake yeast, also known as compressed yeast or fresh yeast, is sold in compressed cakes. It is a highly perishable product that must be kept in in the refrigerator.

This product contains fresh yeast cells that are in an awake state due to the moisture present. To use fresh yeast, you can crumble it into the dry ingredients or dissolve it into the liquid for the recipe.

Fresh yeast only has a shelf life of about 2 weeks, therefore many grocery stores do not carry it. If a store does carry it, cake yeast is typically found in the refrigerator section of the grocery store near the milk, sour cream, and eggs. 

Dry Yeast

Dry yeast is a commercially made form of yeast. The yeast cells have been dried out and therefore are in a dormant state. This makes dry yeast shelf stable and gives it a much longer shelf life than fresh yeast. Dry yeast is sold in two main forms: Active Dry Yeast & Instant Yeast.

Active dry yeast  and rapid rise yeast function essentially the same, with the main difference being the rate of activity. Active dry yeast contains larger yeast cells that function a little slower than the smaller yeast cells found in instant yeast. Rapid rise yeast is highly active when it first wakes up and slows down over time, therefore it is not recommended for recipes where the shaped dough will be refrigerated for a long period of time. 

At one point in time, active dry yeast needed to be hydrated in the liquid before adding it into the recipe. However, these days it can go straight into the dry ingredients just like rapid rise yeast can. If you are adding the yeast into the dry ingredients you want to use liquids that are around 120-130 degrees F. If you are proofing the yeast, you want to keep the liquid temperature around 110-115 degrees F. 

Proofing Dry Yeast

Proofing your yeast is a process of hydrated dry yeast in liquid and adding a pinch of sugar. This process wakes the yeast up from its dormant state and gives it a food source to feed on. This is a way to make sure your yeast is for sure alive and also gives the yeast a jump start so it is very active when it is added into your recipe. 

To proof your yeast, take about 1/2 cup of the liquid from your recipe and warm it to 110-115 F. Add a pinch of sugar  and a 7 gram package of yeast to the liquid. Stir it all together and wait about 5-10 minutes. The yeast mixture should being foaming quite a bit. If you do not see foaming, then you need to get some fresh yeast. If you do see foaming, use the yeast in your recipe immediately. 

How Yeast Functions in Baking

Yeast needs two main things to thrive: moisture and a food source. When yeast is put into a bread dough it begins feeding on the sugars and starches in the dough to create carbon dioxide gas and alcohol. 

Yeast is temperamental and is sensitive to temperature, time, and other environmental factors. I want to go through how yeast responds to different elements in baking so you can be successful and confident in working with it!  

How Yeast Interacts with Temperature

Yeast is very sensitive to temperature. Cold temperatures slow yeast activity down which is why yeast dough is often put in the refrigerator for a long period of time. This process is called “retarding the dough” and is done to accommodate baking schedules as well to improve the flavor of the dough. 

Warm temperatures speed up the activity of yeast. Dough that is proofing in the refrigerator will take much longer than dough that is proofing next to a preheating oven. Once temperatures get too hot, yeast begins to die. Yeast starts to die around 140 degrees F. 

How Yeast Interacts with Moisture

Yeast needs moisture to thrive. Dry yeast is in a dormant state because of the lack of moisture and fresh yeast is awake because moisture is present. 

Liquid will wake dry yeast up and put it in an active state, however it still needs a food source to really thrive. 

dry yeast being hydrated

How Yeast Interacts with Sugar and Flour (Food)

Yeast feeds on sugars found in bread dough. If a bread dough doesn’t contain actual sugar, it will feed on the starches that break down into sugar once they are hydrated. 

When yeast is given moisture and a food source it starts feeding. As it feeds, it creates carbon dioxide gas which makes our bread dough rise, as well as alcohol which flavors our bread dough. 

yeast dough proofing

How Yeast Interacts with Salt 

Salt is a crucial ingredient when working with yeast, because it helps to control the rate of the yeast activity. A bread dough made without any salt would not only taste very bland, but would likely overproof very quickly. 

Salt can also kill yeast in very high quantities. You wouldn’t want to add your salt into the liquid you proofed your yeast in and I always try to keep them separated during mixing so the salt doesn’t inhibit the yeast activity too much. 

yeast dough being mixed

Troubleshooting: What can you do if your dough isn’t rising?

  • Your yeast may be too old. Try proofing your yeast and see if it is active. If it does not foam up, you should toss it and get some fresh yeast. 
  • Your room may not be warm enough. Set the bowl next to a heating oven to provide some warmth.
  • Your water may have been too hot and may have killed the yeast. Make sure the water is warm but not hot. You can use a thermometer to check for a temperature that is between 105F-110F.

Other FAQ About Yeast

  • What does it mean when a recipe calls for one package of yeast?: When a recipe calls for 1 package it is referring to a 7 gram package of yeast. Single serving dry yeast packages are typically sold in a strip of 3, so you would want to use one 7 gram package from the strip of 3. 
  • How can you substitute bulk yeast for 1 package of yeast?: You can substitute 2 1/4 tsp dried yeast for one 7 gram package. 
  • How do I avoid killing my yeast? The number one thing that kills yeast is heat. I would highly recommend getting a kitchen thermometer to take the temperature of your liquid. If you do not have one, the liquid for your bread dough should be very warm but not hot. If it is too hot for you, it is too hot for the yeast. 
  • Can I add more yeast to my dough to make it rise faster? Technically, adding more yeast to your dough can make it rise faster. However, I would encourage you to stick to the amount of yeast the recipe calls for. Too much yeast in the dough can cause it to over-proof. And the yeast can also run out of food, resulting in a loaf that doesn’t rise after being shaped.  
  • What is the best way to store yeast? Dry yeast can be stored at room temperature when unopened. Keep it in a cool place, away from the oven. Once yeast is opened it should be moved to the refrigerator or freezer and kept in an airtight container.