How to proof yeast

When making breads, you should ALWAYS proof the yeast.   If the recipe calls for water, sugar, and yeast, you have no excuse not to, and if the yeast is dead you have just saved yourself from wasting other ingredients.

If done properly, this also ensures that the yeast is fully dissolved and as such will be distributed evenly within the dough.


First, measure out the amount of water the recipe calls for in a glass measuring cup.  Hot water from the tap is fine.  We'll let it cool to the right temperature before adding the yeast.

Now add the sugar and dissolve.  Put an oven thermometer into the mix and wait for the temperature to drop to about 115 degrees Fahrenheit.  If its too cool, microwave the water/sugar mixture for about a minute and remeasure.   You want it to cool to 115, but you don't want to start much cooler than that.  If the water is too hot, you'll kill the yeast.  If it's too cool, the yeast wont activate.

Measure the yeast into a small glass.   While stirring constantly, slowly add the yeast to the water.   This will prevent the yeast from lumping up and will ensure that it is completely dissolved.   The resulting solution should look like muddy water with no lumps of yeast about.

Let stand for about 5 to 10 minutes.   You should see some foam on top of the water.  Your yeast is alive and well and is ready to be added to the rest of the recipe.

If this doesn't happen, the yeast is dead.   Good thing you found out now rather than having dough that doesn't rise, taking with it to the grave any ingredients you mixed it with.