Yeast
Yeast is a living fungus that makes bread rise. Fresh, active dry and instant yeast explained, with conversions, temperatures and what goes wrong.
Also called Baker's yeast, Fresh yeast, Active dry yeast, Instant yeast, Jäst.
Yeast is a tiny single-celled fungus. Baker's yeast feeds on the sugars in flour and gives off carbon dioxide and a little alcohol. The gas is trapped in the dough's gluten and makes bread rise. The fermentation also builds flavor. Yeast is alive, so temperature and time matter.
How to use it
There are three common forms:
- Fresh yeast (compressed yeast) is a soft, beige block that crumbles. It is common in Swedish and other European shops. Crumble it into lukewarm liquid and stir until it dissolves.
- Active dry yeast is in small granules. Traditionally you dissolve it in warm water, about 38 to 43°C (100 to 110°F), with a pinch of sugar and wait 5 to 10 minutes until it foams. This is called proofing the yeast.
- Instant yeast is finer and can be mixed straight into the flour.
Conversion, by weight:
| Fresh | Active dry | Instant |
|---|---|---|
| 25 g | about 9 g | 7 g (one packet, 2¼ teaspoons) |
| 50 g | about 18 g | about 14 g |
Substitutes
For quick breads, use a chemical leavening such as baking powder, though the result is a soda bread or scone texture, not yeasted bread. A sourdough starter can raise any bread but takes far longer and changes the recipe.
How to store it
Keep fresh yeast wrapped in the fridge and use it within about two weeks. It should smell pleasant and crumble easily. Gray, sticky or sour-smelling yeast is past it. Keep dry yeast sealed in a cool place, and in the fridge or freezer once opened.
Common mistakes
- Liquid that is too hot. Yeast dies at around 60°C (140°F). Lukewarm should feel barely warm on your wrist.
- Too much yeast. The dough rises fast but tastes beery and can collapse.
- Rising in a cold room. It works, just slowly. Give it more time.
In recipes
Swedish recipes are written for fresh yeast, jäst, and say to dissolve it in liquid that is fingervarm, about 37°C (99°F). Shops sell yeast for savory dough and a separate kind for sweet dough (jäst för söta degar), which copes better with the sugar and butter in buns. Do not confuse baker's yeast with nutritional yeast, which is inactive and cannot raise dough.
Recipes that use it
4 recipes from the sites we collect.
Related terms
- ProofTo proof is to let shaped dough rise one last time before baking. Use the poke test to tell when bread is ready, underproofed or overproofed.
- LeaveningLeavening is what makes dough and batter rise, such as yeast, baking soda, baking powder, steam or whipped air. Here is how each works and when to use it.
- Bulk fermentationBulk fermentation is the first rise, when bread dough ferments in one mass before shaping. It builds flavor and strength. Here is how to judge it.
- KneadTo knead is to push, fold and turn dough until it is smooth and stretchy. It builds gluten so bread rises well. Here is how long it takes and how to tell.
- Sourdough starterA sourdough starter is a fed mix of flour and water full of wild yeast and bacteria that leavens bread. Here is how to make, feed and store one.
- Nutritional yeastNutritional yeast is a dried, inactive yeast sold as yellow flakes. It tastes cheesy and nutty, and it gives vegan sauces and popcorn savory depth.