All About Active Dry Yeast: How to Use Active Dry Yeast

Active dry yeast is a dried, granulated form of baker’s yeast, a species of single-celled microorganisms known as *Saccharomyces cerevisiae* that consume sugars and starch and produce carbon dioxide gas and alcohol as a result. This carbon dioxide gas becomes trapped in the interior structures formed by gluten strands during the baking process, making bread and other baked goods rise. The most common yeast you’ll find at grocery stores is individual packets or glass jars of active dry yeast. This store-bought yeast has a longer shelf life than blocks of [fresh yeast](https://masterclass.com/articles/fresh-yeast-explained) (or cake yeast) when sealed and kept at room temperature, and is dormant until activated by warm water. Instant yeast, also known as rapid rise or quick rise, and active dry yeast are essentially the same ingredient, in slightly different forms. Fast-acting [instant yeast](https://www.masterclass.com/articles/instant-yeast-vs-active-dry-yeast) is ground to a finer particle size and exposed to a gentler heat in the drying process, which keeps the majority of the yeast cells alive. As a result, instant yeast can be mixed directly into dry ingredients ([proofing](https://www.masterclass.com/articles/baking-101-what-is-proofing-learn-how-to-proof-breads-and-other-baked-goods) it in a warm liquid will only waste its ability to rise quickly), allowing you to skip the first rise time and shape loaves immediately after [kneading](https://www.masterclass.com/articles/kneading-techniques). Conversely, active dry yeast contains larger particles that you must dissolve and rehydrate in warm water for the proofing process. Commercial active dry yeast is made by introducing a “seed yeast”—a curated, lab-cultivated strain kept separate from naturally occurring wild yeasts—to molasses and starch. This yeast is then allowed to ferment before being separated from any extra water or byproducts and washed. The resulting yeast sludge, or “cream yeast,” is then dried under extreme heat and ground into small particles before being portioned into packages. This process kills about a quarter of the yeast cells, forming a protective coating around the living ones, effectively forming a barrier that must be broken down by proofing before activating the remaining living cells. You must proof active dry yeast before using it in a [bread recipe](https://www.masterclass.com/articles/how-to-make-homemade-bread-tips-and-easy-recipe). 1. To proof the yeast, prepare a ¼ cup of warm water no warmer than 110 degrees Fahrenheit, add a teaspoon of sugar, and the amount of yeast the recipe calls for. 2. Give the mixture a quick stir, then allow it to sit for 5–10 minutes. If the yeast is alive, it will begin to foam and bubble. 3. You can then incorporate the activated yeast mixture into the bread dough. Active dry yeast becomes perishable when exposed to water or air. Store any leftover yeast in an airtight container and refrigerate for up to three months. We’ve got you covered. All you knead (see what we did there?) is The [MasterClass Annual Membership](https://www.masterclass.com), some water, flour, salt, and yeast, and our exclusive lessons from Apollonia Poilâne—Paris’s premiere bread maker and one of the earliest architects of the artisanal bread movement. Roll up your sleeves and get baking. Many homemade bread recipes call for a few teaspoons of active dry yeast—one of the most approachable and easy-to-use types of yeast available.