Are all types of yeast the same? Are they all gluten free? The answer to both of those questions may seem obvious. No for the 1st question and yes for the 2nd. But I would not be writing this post if it was that simple.
There are 4 main types of yeast, active dry, instant, fresh and wild (sounds like a catch phrase in a deodorant ad). Each type works differently, is stored differently and has it's own shelf life. Only 2 matter to the home baker, active dry and instant (unless you work with sourdough in which case you will be using wild yeast).
Active dry yeast needs to be "activated" before adding to dough. That is usually accomplished by adding the yeast to a mixture of liquid and sugar. Once the mixture is bubbling and foamy it is ready to be used. It works well with recipes that call for a double rise and a longer proofing time. A little note here, there are some who now state that active dry yeast can be added directly to the bread dough with the dry ingredients. Since this is meant to be used in recipes that need a longer proofing time, there may be validity to this claim.
Instant yeast broadly covers Rapid Rise and Bread Machine yeast. These are added directly to the dry ingredients in your recipe. Once liquid is added the yeast will begin to work. It's easy to use and a favorite among home bakers.
Brands vary in what they classify under the heading of Instant Yeast. For some Rapid Rise is not the same as a packet labeled Instant. Some are best for only one, quick rise, the dough is placed in the tin immediately after kneading and in the oven when risen.
There is also Osmotolerant Instant Yeast used for baking an exceptionally sweet dough like cinnamon rolls or brioche. Sugary dough often takes a long time to rise because sugar can starve the yeast of water hindering it's growth. A special strain of yeast that requires less water to work is preferred in this situation. Check out SAF Gold Instant Yeast.
Finally, a few brands of yeast contain dough enhancers and these are not always gluten free.
What type of yeast should be used to bake Gluten Free Bread?
Active dry yeast and instant yeast both work well and are often interchangeable. Be on the lookout for any Rapid Rise yeast that is best for one rise. For most of us that's the way gluten free bread is baked, a single rise in the tin. However if you are going to rest your bread or employ a technique where there will be a longer proofing time, use yeast that works best in that circ*mstance.
To work through the confusion check the manufacturer's website for more info.
As an example check out the brand SAF
Happy Baking!
