Active Dry Yeast, Instant Dry Yeast And Cake Yeast: What’s The Difference?

A common question asked once one begins to get into baking bread is “What the difference between Active Dry Yeast, Instant Dry Yeast, and Cake Yeast?” Well, look no further, because this article was specifically designed to answer this common baking question.

Active Dry Yeast

Active dry yeast is cultivated in large tanks. When it’s harvested, yeast is dried in the form of compact granules and then covered with a protective coating of yeast “debris.” The yeast can be stored at room temperature for months, although its strongly recommended that you store it in your fridge. If you have more than three months worth of yeast, you can store it in the freezer.

Active dry yeast is reactivated by soaking in warm water (about 105-110 F). Hydrating the yeast at a lower temperature leads to inconsistent results and can also inhibit the proper gluten formation.

Instant Dry Yeast

Instant dry yeast was an innovation of the 1970s. The yeast is dried much faster then active dry yeast, and on a microscopic level they resemble porous rods that rehydrate much more efficiently then the dense granules of active dry yeast. Because of this innovation, instant dry yeast does not need to be re-hydrated before being mixed into bread doughs.

Cake Yeast

Cake yeast comes in a compressed cake form (hence the name) and is mostly used by professional bakers or extremely ambitious home cooks. Its a little inconvenient for the average home cook because its somewhat hard to find and is perishable, with a shelf life of 1-2 weeks.

The yeast cake itself actually contains live yeast cultures, which is why its important to keep it chilled, and is a much more powerful leavening agent then the other previous forms of yeasts discussed above. For this reason, you will have to reduce the amount of cake yeast used in a recipe that calls for instant dry yeast or active dry yeast.

For more information on yeast and other bread baking ingredients, listen to The Free Culinary School Podcast Episode 18| Sourdough Starters and Pre-Ferments.