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https://www.thekitchn.com/how-to-make-your-own-sourdough-starter-cooking-lessons-from-the-kitchn-47337 PUBLISHED: FEB 24, 2014Zu den englischen Masseinheiten:
Not all of us are so lucky to have a sourdough starter passed down to us from our bread-baking forefathers and foremothers. Thankfully, making a fresh batch of starter is as easy as stirring together some flour and water and letting it sit. That’s right!
No expensive heirloom starters, mashed-up grapes, or mysterious rituals required — just flour, water, and a little bit of patience. Here is how to make your own sourdough starter from scratch. Easy-peasy.
Before you get started, let’s talk about wild yeast, which is the key to a sourdough starter
Before we had active-dry yeast or instant yeast, we had wild yeast. Actually, we still have wild yeast. It lives everywhere — in the air, in a bag of flour, on the surface of grapes. Domesticated commercial yeast replaced wild yeast for most baking because it’s easier for companies to mass produce, it’s easier for bakers to store and use, and it proofs our breads and pastries in a fraction of the time.
By contrast, wild yeast can be fussy and finicky. It needs a medium, a sourdough starter, in order to be useful to bakers. This medium has to be constantly maintained and monitored. Wild yeast also likes cooler temperatures, acidic environments, and works much more slowly to proof breads.
So why bother? Because wild yeast is amazing stuff! The flavor and texture we can get from breads and other baked goods made with wild yeast are no contest to breads made with commercial yeast — the flavors are more complex and interesting, the texture is sturdier and more enjoyable to chew.
A sourdough starter is how we cultivate the wild yeast in a form that we can use for baking. Since wild yeast are present in all flour, the easiest way to make a starter is simply by combining flour and water and letting it sit for several days. You don’t need any fancy ingredients to “capture” the wild yeast or get it going — it’s already there in the flour. (Also, the yeast adapts to whatever environment it is in. So even if your cousin in San Francisco gives you some sourdough starter, it will eventually no longer be true San Francisco sourdough, but rather New York sourdough or Austin sourdough or London sourdough.)
After a day or two, bubbles will start to form in the starter, indicating that the wild yeast is starting to become active and multiply. To keep the yeast happy, we feed the starter with fresh flour and water over the next several days, until the starter is bubbly and billowy. Once it reaches that frothy, billowy stage, the starter is ready to be used.
Read more: What’s the Difference between Levain and Starter?
This recipe uses regular, everyday all-purpose flour, but you can certainly make sourdough using whole-wheat, rye, or any other kind of flour. Wild yeast is everywhere, after all!
If this is your first time making sourdough, I’d recommend starting with all- purpose flour because it tends to behave the most predictably. If you’re feeling ready to branch out, just start feeding the starter with whatever whole-grain flour you would like to use for baking. Personally, I keep a constant batch of all-purpose sourdough starter in my kitchen, and if I want to make a rye starter or a whole- wheat starter, I scoop 1/4 cup from my all-purpose starter and use that as the seed for a new starter with the whole-grain flour.
This starter uses equal parts flour and water, a 1:1 ratio, which I find to be the most versatile for baking. To use this starter in any recipe, take a look at the ratio of flour and water the recipe is calling for in their starter. Next time you feed your starter, just feed it the ratio of water and flour called for in the recipe. If you want to stick more closely to the recipe’s sourdough, just scoop out 1/4 cup of your starter and feed it with the ingredients called for in your recipe’s starter.
Once you’re done with your recipe, go back to feeding your starter equal parts flour and water.
Preferments can be sorted into two main categories.
Preferments made with commercial yeast, which are mixed about a day before you mix the dough and used entirely.
Preferments that contain wild yeasts and bacteria, which are maintained and then increased when needed for bread and used over and over.
The second type of preferment is what we’ll refer to as sourdough starter and what we’ll look closer at to understand some of the science of sourdough.
A sourdough starter is created by mixing flour and water, and then allowing the microorganisms — wild yeasts and bacteria — that live in the flour and air to thrive and multiply. Over time, a stable population of these microorganisms develops. When used in bread, the microorganisms perform fermentation reactions, producing the gas that makes the dough rise and the molecules that give it flavor. These flavor molecules are different than those produced by commercial yeast.
In spite of the name, not all sourdough breads have a sour flavor. Time, temperature, and the presence of various types of bacteria can affect the final flavor.
Time: A sourdough loaf baked the same day it is mixed will have a milder flavor than one that had a longer fermentation time. Some bakers even recommend using less starter in the recipe to extend the time it takes the dough to rise.
Temperature: Different rising temperatures affect the activity of the yeasts and various types of bacteria, resulting in different flavors. Francisco Migoya, head chef and coauthor of Modernist Bread, shared that proofing at cold temperatures (that is, putting your dough into a fridge overnight) generally results in a harsher acidic flavor, while letting your dough rise out of the fridge results in a more mellow acidic flavor. Many bakers use combinations of the two temperatures; experiment with rising temperatures until you find the flavor you like best.
Location: It’s long been thought that the location where a starter is created affects its flavor. Research now shows that this might not be the case; the flour and conditions used are what’s important. (We’ll discuss this more in an upcoming post on the myths about sourdough starter.)
Flour: Different types of flour can be used to create a starter: white, whole- wheat, rye, and others. The type of flour depends on what kind of bread you plan to make. For example, if you want to make a 100 percent rye bread, you’d need to maintain a rye starter. Sourdough starter made with white flour is the most common type.
Wet vs. Dry: Different starter consistencies can be used. A wetter starter, which looks more like batter than dough, is more reactive, while a drier, dough-like starter is better for storing for longer periods in the refrigerator. Some bakers say that a wetter starter has a milder flavor, but Migoya’s team found that a wetter starter produced a more acidic bread, with a stronger sour flavor. A wetter starter can more easily be mixed into dough. I found a drier starter easier to work with in the days before I had a scale, when I had to estimate the amount of starter used in dough; the dough-like consistency affected my dough less if my measurement was off.
I highly recommend weighing all your ingredients when making sourdough bread. Not only is this more accurate, but it’s also ultimately easier. When weighing, all you have to do is dump ingredients in the bowl and watch the scale
— plus there’s no guesswork about did I just add the fourth or the fifth cup of flour?
This said, I don’t want this to deter you from trying a loaf of sourdough for yourself. If you’re more comfortable working in cups and tablespoons, those measurements are here for you too. It’s less accurate, but the recipe is forgiving and a few extra or a few fewer grams here or there isn’t going to affect much.
We already made the sourdough starter, so now we make the leaven — this “leaven” is ultimately what gets mixed into the dough. It’s made with a tablespoon of your active starter and a specific amount of flour and water. A tablespoon of starter might not seem like much, but you’ll be surprised at how quickly the yeasts in that tablespoon multiply and make the leaven bubbly!
Make the leaven the night before you plan to mix the dough and leave it on the counter. By the next morning, it should be bubbly and smell slightly sour. You can test that it’s ready by dropping a spoonful into a cup of water; if it floats, it’s ready!
The Autolyse
After you’ve mixed the leaven with the remaining flour and water, let it sit for at least 30 minutes or for up to four hours. During this time, the flour absorbs the water and becomes fully hydrated, which helps gluten formation during the next step. Enzymes in the flour also start to break down the starches into simpler sugars, which become food for the yeast and bacteria in the leaven and also make the bread more flavorful.
After this resting step, mix in the salt. Salt is necessary for a flavorful bread, but can inhibit the activity during the autolyse step.
After trying a great many different sourdough recipes over the years, I have become a big advocate of the folding method for developing the gluten in the dough, rather than kneading in a stand mixer or by hand. Folding is not only less labor intensive, but it also gives the crumb of the finished bread a better structure and a nicer network of holes (which are a good thing in the artisan bread world!).
After the autolyse, begin folding the dough by grabbing some of the dough from the side, stretching it up, and then folding it over on top of the dough. Do this a few times around the bowl, then let the dough rest about 30 minutes before doing it again. After a few rounds of this, the dough will go from shaggy and clumpy to smooth and stretchy.
Proofing baskets support the shaped loaves during their final rise before baking. You can buy the same kind of rattan or wicker proofing baskets that bakers use, or you can simply use a colander or a mixing bowl. In either case, line the basket or bowl with a clean dishtowel and coat it generously with flour. Use your fingers to rub the flour into the cloth — this is what will keep the dough from sticking.
Proofing baskets don’t need much maintenance. After you’re done baking, knock out any loose flour, let them dry on the counter, and then store them in a cupboard. If you bake fairly frequently, you don’t need to wash the dishtowel — in fact, letting the flour build up will help prevent the dough from sticking. Keep an eye out for mold, though, and always let the cloths and the baskets dry thoroughly before storing them again.
Dutch ovens are a boon to home bakers. You need a moist, humid environment during the first few minutes of baking to get a good rise from the dough and to develop the crust, but making that happen in home ovens is tricky and imperfect. Dutch ovens solve the problem. Dutch ovens trap the moisture evaporating from the bread and create its own steamy environment. Once the initial baking phase is over, you uncover the pot to release the excess steam and let the bread continue baking.
If you don’t have a Dutch oven, you can use any heavy pot with a lid, like a soup pot or even a large saucepan.
This whole process, from mixing the initial dough to baking the bread, is a long, slow, drawn-out affair. You can do it in a day if you’re at home and feel like tinkering around in the kitchen for a few hours, or you can spread the process out over a few days. There are a few moments in the recipe where you can pause and put the dough or the shaped loaves in the fridge overnight. This time in the fridge actually helps develop the flavors in the dough even more!
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