Leaven Life: Bakers' Yeast

Whenever you have aficionados you have snobbery. It’s inevitable. Artisan bread baking aficionados are snobby about their leavening. They think natural leavening (sourdough) is the shit. Bakers yeast is not.

Bakers yeast is what most people bake with. It’s the stuff you find in the baking aisle at the grocery store. Most people use the dried kind, which either comes in packets or small jars. The yeast looks like tiny-tiny tan twigs. You can also sometimes find little cakes of yeast in the refrigerated section. They usually come in one ounce cubes.

This yeast is domesticated. Domestication is what we do to genetically modify our food, and we’ve been doing it for thousands of years.

Take dogs. We can breed dogs to look a certain way. If we're looking at a group of, say, Cockerspaniels, we might decide that we like the ones with longer hair. And if we want the next litter of puppies to have longer hair, we pick a long haired male and longhaired female to breed. It’s more likely that the litter from this couple will have longer hair than the litter from two shorter haired spaniels. Inheritance. Genes. DNA.

We’ve been intentionally doing this with plants for more than ten thousand years. Wheat was just a prairie grass that looked nothing like today’s domesticated grain. We've coaxed bitter, meager wild fruit into the buxom market variety we eat today. By picking and planting the individuals we like, nature has obliged and given us protein rich grains, sweet fruits, and starchy vegetables.

Bakers domesticated yeast by selecting for a strain that eats quickly and farts a lot. (Brewers have done the same thing to get lots of alcohol out of their yeast.) When you catch yeast out of the air and first start using it in your sourdough recipes, you have to wait a long time for it to inflate your bread.

Typically when you make bread, you mix your dough, knead it, and let it sit for a while before you form the loaf. While it sits, it inflates to about twice its original size. With your recently captured wild yeast, this will take maybe 4 to 6 hours, or longer. With bakers yeast, and a warm temperature, it'll take as little as 30 minutes. Obviously this makes things a lot easier, since bakers' yeast speeds up the process and has a fairly consistent rate.

So why use natural leavening? For one thing, you get a more interesting pattern of bubbles in the dough. And by "interesting", artisan bakers mean non-uniform bubbles. They really like big bubbles. Cut a good sourdough loaf in half and you should get a few huge holes, some medium sized ones, as well as the more uniform smaller holes. Bakers yeast will give you pretty much just uniform smaller holes.

Another thing is the taste. Sour dough is a bit sour, though it shouldn't be overwhelmingly so. Sometimes it's described as tangy and maybe a bit "nuttier" than breads made with bakers' yeast. But as a sourdough starter matures, it becomes less tangy and tart. It shouldn't really be all that sour, but the taste is distinct.

Sourdough also gives a thicker, crispier crust to breads. If you're into that.

I end up using bakers' yeast much more often than natural leavening, just because I don't always have 6 to 10 hours to baby-sit a slowly bloating lump of dough. But when I have the time, it's worth it.

Leaven Life: Sourdough

Yeast is familiar to us for a few reasons, the most appetizing being their critical role in making beer, wine, and bread. At some point, people discovered this cute little trick that yeast does. It eats sugar, shits alcohol, and farts COtwo. (Did I say this was appetizing?)

Yeast is in the air. Many moons ago, probably somewhere in Egypt or Mesopotamia, someone mixed ground wheat with water to bake over a fire. The paste was left out for a while, and when it came time to bake, they found the dough was like twice the size it was before. Yeast farts. When you bake the dough after yeast has done its thing, you get a lighter, spongy-er bread that’s pretty tasty.

The yeast/gas action is known as leavening, a word most of us were probably first exposed to in its negative form: unleavened bread. The Jews use unleavened bread for their Passover celebration. Maybe it was because of those Egyption bastards who had enslaved them. Leavening was probably all the rage along the Nile, and the Jews were like, look at those assholes with their asshole bread all ballooned out and stupid looking. What assholes. Hence, unleavened bread for the Passover.

You can do this today. Mix a cup of flour and a cup of water together in a container and let it sit in the open air for a few hours. Then put a loose-fitting lid on the container, let it sit for a few days, and watch what happens. It starts bubbling. This is COtwo. You have enslaved yeast to build your pyramids of French bread.

Now, it’s kind of hard to do this in Indiana. Some places are famous for the ease with which you can capture yeast out of the air and create a sourdough culture. San Francisco is one of these places. The Midwest is not. I’ve tried to do this several times, and have only been successful once.

[There are also people who think the "yeast in the air" theory is bullshit, and that the yeast is actually already in the flour when you mix it with water. I prefer the airborne yeast theory because it is demonstrably cooler.]

The recipe I used that worked (can't find it at the moment, but there are a bunch online, along with this great article on the topic) called for pineapple juice. This is supposed to create the optimal environment for yeast to survive in your petri dish. Specifically, it produces an acidic environment, which is good for yeast and apparently bad for bacteria. That’s what’s happening in your container there, a battle between yeast and bacteria, and you want the yeast to win. But there’ll always be a little bacteria in your starter, as you keep this bubbling goo going for years and years.

After 3 days or so, you start “feeding” the thing, which means you add equal parts water and flour and stir it up. You’re adding food (sugar) for the yeast to keep them alive, but as I said, some bacteria will stick around in small amounts. The buggers just won’t go away, and that’s what gives the sour flavor to sourdough bread.

Leaven Life: Yeast

The first quantum revolution was in Biology.

Physicists first started using the word "quantum" in the early 20th century as a way to describe the basic make-up of our universe at the smallest scale.

There was a nagging unanswered question scientists and philosophers had been asking about physical reality for millennia. If you break matter down to smaller and smaller chunks, will you get to the smallest chunk possible, the basic building blocks of matter, or not? Is matter infinitely divisible? We are familiar with the answer to that question now. Matter is made of atoms, and smaller atom like particles, so yes, matter is made of building blocks.

And energy, it turns out, comes in small packages as well, called quanta (plural form of quantum). It is quantized. It all fits together with the e-equals-emcee-squared concept. Matter and energy are equivalent and ultimately grainy, pixelated and, at the smallest scale, freakin weird. We refer to this discovery about physical reality as the quantum revolution.

But the living world is also quantized. Everything that is alive is made up of a bunch of small building blocks called cells. Your cat, the tree in your lawn, the ants on your floor, the mold on your bread, they’re all made out of a bunch of little blocks, or sacks, with molecules inside. Cells can combine to form all kinds of shapes and sizes, organs and organisms, one of the most complicated being homo sapiens and their conscious brain.

If you chop up a living creature, you will eventually get to the smallest chunks they are composed of, the cells. Of course, you can chop up cells too and look at the molecular stew inside, but at that point we aren’t looking at the biological world anymore. The point is that plants and animals aren’t just homogenous bodies which can be divided in any old way. We are made of organs made of cells, which are then, yes, tiny bags of chemicals.

Robert Hooke discovered the first cell back in the 17th century, and the cell theory of life was first proposed in 1839 by a couple'a German guys. It seems like we don't hear as much about this revolution as we do about quantum physics, but it was just as epoch making. Our bodies are communities of trillions of tiny living blobs. Weird.

Life on earth began when the first cell came into existence. It took a while for single cells to start congregating to form multi-celled organisms, but there have always been single celled organisms hanging around since the big-biological-bang. One of them is bacteria. Another is yeast. And yeast, my friends, is what gives life to bread.