I’m talking about yeast, people. Single-celled little fungi, yeast live to eat sugar, make alcohol and produce gas. Oh, and reproduce. And that’s pretty much their whole raison d’etre. Yeast is necessary in wine making, beer making and bread making. We shan’t concern ourselves with the liquid breads–I’m more interested (at the moment, anyway) in what yeast does for bread.
Please don’t be intimidated by yeast. They are much smaller than you, and you have opposable thumbs and a forebrain. You are smarter than yeast, so fear not!
There are a couple of Things to Know about yeast:
1)Like people, yeast doesn’t like to be too hot or too cold. If they get too cold, they just lie there, dormant and hibernating. If they get too hot, they die. Either way, your rise won’t happen unless the yeast are in their temperature comfort zone. Fortunately, yeast’s comfort zone is kind of like our comfort zone. They’ll perform nicely at around body temperature. At temperatures abovoe 140 degrees, F, they die. At refrigeration temperatures, they fall asleep. You can adjust rising times by manipulating the temperature of the dough, but I’m getting ahead of myself.
2)The power that yeast has to make liquids ferment and doughs rise has been harnessed for thousands of years. There is always some sort of yeast hanging out in the environment around us. Capturing and taming wild yeast gives us sour dough starters and breads. Commercial yeast is much less dicey to deal with–you always know what you are getting. Yeasts like it best in environments whose pH is neutral or just slightly acidic. Too much acid, and they won’t grow. Too much alkali, and they won’t grow. This is generally not a problem since most yeast dough recipes fit yeast’s preferred pH profile. No surprise there.
So, What’s All This About Proofing?
Proofing yeast just means mixing it in some warm water so it can start getting bubbly and PROVE to you that it’s alive. Seriously, that’s all it means. If you’re going to proof your yeast before continuing with your recipe, toss in just a teaspoon or so of sugar or honey with the warm water. This will make the yeast happy as they will have something to snack on.
Is There Some Sort of Mysterious Secret About Making Bread?
Not so much. If there is a secret, it’s to relax. In almost all cases, use a high protein flour–either a very sturdy all purpose flour, such as King Arthur, or bread flour. Always put salt in bread. Always. Not only will it make your bread taste good, it also helps to control yeast growth and keep your crumb a little tighter. Sorry, no mystery here. Move along, now, folks.
Speak to Me of the Chemical Process of Fermentation
Um, okay. Fermentation occurs when our yeast friends convert sugar into three things: alcohol, carbon dioxide and heat. Fermentation occurs anaerobically, which means not in the presence of oxygen. That’s about as deep into the chemical process as I am able to want to go, but note this: one of the by-products of fermentation is heat. This heat will make the yeast happy and they will reproduce faster. If you want to slow this process down, you’ll need to refrigerate your dough.
Admittedly, this little primer just scratches the surface of what yeast does/can do. If you have a specific question, don’t hesitate to ask. Otherwise, we’ll pick up here tomorrow right where we left off. Stay with me, there’ll be a loaf of bread in it for you if you do.