Is it just me or do all these kinds of yeast sound suspiciously similar? I've been baking and buying yeast for years, and sometimes the yeast choices in the baking aisle still get me confused!
Here's the thing: Yes, there is a difference between all these varieties. And yes, which one you use does make a difference in your recipe.
The Difference Between Active Dry Yeast & Instant Yeast
The difference between these types of dry yeast is simple: active dry yeast has a larger granule and needs to be dissolved in water before using, while instant yeast has a more fine texture and can be mixed right into dry ingredients.
More About Active Dry Yeast
This is probably what comes to mind when you think of yeast. It's a type of dry yeast that's granular, with a consistency similar to cornmeal. It's a living organism that's dormant until proofed, or dissolved in a small amount of lukewarm warm water (about 110°F). It's then added to the rest of the ingredients, where it will cause dough to rise.
Active dry yeast is typically sold in individual packets (pictured here) or small jars.
More About Instant Yeast
Instant yeast is another type of dry yeast that was introduced after active dry yeast in the 1970s. It is made using a similar process as active dry yeast, although is dried more quickly. As you can see, this yeast is also milled into finer particles. Because of this, it dissolves faster and activates quickly. But unlike active dry yeast, instant yeast doesn't have to be proofed first; it can be mixed straight into the dry ingredients with the same result.
This yeast also gives you two separate rises and it can be used interchangeably with active dry yeast.
More About Rapid-Rise Yeast
Instant yeast may also be marketed and sold as rapid- or quick-rise yeast. This yeast has also been milled into smaller particles so it doesn't need to be dissolved into water. In addition, enzymes and other additives are included to make the dough rise faster. With this yeast, you can skip the first rise of the dough and shape the loaves right after kneading.
Which Type Should I Use?
This part is really up to you. While each type of yeast reacts differently and produces baked goods with slight variations, there's no one right answer.
Active dry yeast and instant yeast can generally be used interchangeably, one-for-one (although active dry yeast may be slower to rise). So if a recipe calls for instant yeast and active dry yeast is used instead, you may want to consider adding an extra 10 to 15 minutes for the rise time.
I recommend picking one kind of yeast, becoming familiar with it, and using it in everything unless the recipe gives a specific reason to do otherwise.
This past has been updated — first published June 2008.