I am making bread and my yeast is not foaming. I am using water at 110 F and my yeast is good - I recently used it a couple of days ago, and it worked fine. This time, it looks like brown water; it has dissolved, but never foamed. I keep my yeast in the refrigerator. Instead of using it right after I have removed it, should I pull it out and let it warm up first? I don't think I pulled it out and let it warm up the last time, but I am unsure.
110F is almost too hot for the yeast. 100F works just as well and leaves a threshold of safety.
You do not have to warm the yeast before placing it into the water.
Try 1/2 tsp of sugar in 50 grams of 100F water to start the yeast. It should be a party in there within 10 minutes. If not, you've got dead yeast.