Baking With Yeast: The Basics

bread dough that has proofed and risen in a clear bowl

Baking with yeast can seem intimidating to beginner bakers. Yes, it can be complex with many nuances you learn as you gain more experience, but that shouldn’t scare the novice baker away from working with yeasted dough. This post outlines some of the basic points of baking with yeast to get you started.

What is yeast?

Yeasts are a type of single cell microorganisms that are part of the fungus kingdom. There are over 1,500 species of yeast, but this post will focus on the yeast species used in baking called Saccharomyces cerevisiae. This species of yeast is also used in beer and wine making. When used in baking, yeast is a natural leavening agent that helps provide rise to doughs.

Types of Yeast Used in Baking

Yeast used in baking comes in three main types:

Fresh: Fresh yeast is sold in solid blocks in the refrigerated section of some grocery stores. To use, you crumble off the necessary amount and let it dissolve in the liquid in the recipe. Fresh yeast must be kept refrigerated and has a short shelf life of about a week, so it is best used for bulk baking.
Active Dry: Active dry yeast is live yeast that has been dehydrated and ground into small granules, often sold in small packets or jars. It can be rehydrated and “bloomed” in warm liquid with a small amount of sugar. This step is not necessary, but it does tell you if your yeast is still active. If the yeast is still active, the mixture will increase in volume and become foamy within about 10 minutes. It has a longer shelf life than fresh yeast.
Instant: Instant yeast is ground slightly smaller than active dry yeast. It does not need to be bloomed prior to baking and can be added with the dry ingredients. Using instant yeast instead of active dry yeast will usually yield a slightly shorter rise time.

What Creates the Rise?

There are two major ways that yeast helps baked goods rise. The first is by creating carbon dioxide. Yeast feeds on sugar and releases carbon dioxide that expands while proofing and baking, causing the dough to rise. Yeast also produces alcohol, specifically ethanol, from breaking down sugar. This alcohol evaporates during baking, creating more gas bubbles that contribute to rise.

The Best Conditions for Yeast to Grow

Yeast thrives in hot and humid environments. Yeasted dough is usually recommended to proof between 75°F and 85°F, depending on the recipe (of course, there are exceptions to every rule). So if you find that your bread is not rising as much or as quickly as you would like, check to see if your proofing environment is too cold. But be careful, there is such a thing as too hot. An overly warm proofing environment can result in overactive yeast and too much rise. Blooming active dry or live yeast in liquid with temperatures above 120°F will cause the yeast to die off.

I hope that basic information helped you learn a little more about baking with yeast. Keep an eye out for future posts getting into more details about yeasted doughs and making a proof box!