Introduction: Real Sourdough Bread

About: I am a chemical engineering undergraduate at the University of New Hampshire. I like to make things.

There is a lot of confusion about what sourdough bread is. Is it bread with a sour taste? Do they only make it in San Francisco? What makes it so different?

Sourdough bread is bread that is leavened using a sourdough culture containing wild yeasts and bacteria. The yeast that can be bought in small packages and jars at the store is commercial yeast . It is one strain of yeast, raised because it is really great for making bread quickly consistently. A sourdough culture will probably contain many different strains of yeast, and several types of bacteria. While an envelope of commercial yeast is innumerable copies of one organism, a sourdough culture is a diverse ecosystem. Because of this, sourdough breads have a more complex flavor and texture than breads made with commercially available yeast.

So where does the "sour" part of sourdough come from? While yeast produce carbon dioxide and alcohol, the bacteria in a sourdough culture produce lactic acid. This give some sourdough breads their distinctive tangy taste. The increased acidity and other compounds produced by the bacteria  make sourdough breads more resistant to mold and staling than other artisan breads.
Although these bacteria can make the bread tangy,  not all sourdough is noticeably tangy. It depends on what bacteria are in the culture being used. However, there are methods that can create the sour flavor that some people enjoy in their bread.

Making true sourdough bread is more difficult, and more time consuming than using instant yeast. That having been said; sourdough creates loaves of bread that have a flavor that can't be matched by breads made using commercial yeast.
It is a common misconception that sourdough bread can be produced using a commercial yeast that is allowed to develop in a batter overnight. This is called a preferment, poolish , or biga . This technique can make really great breads, but it isn't true sourdough and tastes very different. Here I present sourdough bread and describe the techniques used to create it.


Step 1: Assemble Ingredients

First, assemble the ingredients.
A real sourdough loaf is surprisingly simple ingredient-wise. The quality comes from the technique. Of course, having good quality ingredients will help too.


Ingredients
Unbleached Bread Flour
Rye Flour
Water
Salt
Rye Starter


Flours
Bread Flour - This flour is different from regular all-purpose flour in two ways. The first is that it is milled from different wheat, often harvested at a different time of the year. This wheat contains more of the compounds that will form gluten in your bread. Gluten is what makes dough stretchy and bread chewy. The second way bread flour is different is it often contains malt powder. This encourages yeast growth. Not all bread flour will contain this but most commercially-available bread flours in North America have it.

Rye Flour - This is a whole grain flour. It adds complex flavor to breads and is used to feed the starter in this recipe. Rye flour will not form gluten on its own. The more rye flour is in a bread, the more difficult it will be to form gluten while kneading.

Whole Wheat Flour-Not mentioned on the list. It is strictly optional. This is a whole grain, more flavorful flour. Some people find it bitter. Usually when I am making this bread about two cups of what I have listed here are whole wheat flour, I enjoy the flavor. It absorbs water more slowly than white flour.

I recommend practicing the recipe a few times with mostly white flour and then incorporating more whole wheat or rye flour into the recipe.

Water
A lot of people say it is important to use spring water or filtered water or some other water, that chlorinated water will kill your yeast.  I use tap water (yes it's lightly chlorinated) as do most great bakeries I know to no ill effect. If your tap water smells like a swimming pool it is probably better to use spring water or filtered water. I've never had a problem with it.

Salt
Salt is extremely important in bread. Do not omit salt based on the reasoning that it will be healthier. Not that much salt goes into bread. Salt balances the flavor of bread very nicely, if you don't add it your bread will taste strange. Salt also helps in regulating yeast growth. If you don't use salt the yeast may develop inconsistently.
As for what type of salt, I use plain free-flowing salt. Sea salt, kosher salt, Himalayan pink salt; all fine-it won't make a difference in how your bread tastes. I would save the good salt for some other application. If you do use some other type of salt, be aware that 1 Tablespoon of plain salt does not equal 1 Tablespoon of kosher salt. The larger grains change the volume. If you are going to play around with salt types use a scale to make sure it is the same amount.

Rye Starter
This contains nothing but rye flour and water. This is all wild yeast, no stuff from the jar/packet. Don't ever add salt, sugar, pineapple juice, or anything else but flour and water to this. If you wanted, you could easily use your wheat starter for this recipe; it should work but the fermentation times may be slightly different based upon the starter you use.

Step 2: Tools

This is a very minimalist approach to bread production. Most bakeries use machinery to mix, knead, and sometimes even shape their breads. All you will need to produce the bread I have described here are the following items.

Measuring Cups
In this instructable I use both dry and liquid measuring cups to measure the ingredients. These are American measuring cups, slightly different than those used in other countries.
In a bakery, all measurement is done by weight. This is because ingredients like flour can change in volume depending on the type of flour and the compression. If you want to see an example of this take two cups of flour and try to cram it into one cup of flour. It is possible. However, I know a lot of people don't have access to scales, so I am using measuring cups for dry ingredients here. Once you get really good at bread making the inaccuracy doesn't even matter, you can feel when the dough needs more or less flour.

That having been said, to be more accurate please use the following conventions when measuring dry ingredients:
Do not pack flour into the cup, pour sifted flour into the cup. This will make sure you have roughly the same amount of flour as I have used.
Level the cup off. This means filling the cup with flour, and pushing a knife or flat object over the top to make sure the cup is filled to the top and not a bit more. A heaping cup of flour is probably about one cup and a half of flour. If you're measuring 6 cups of flour this way it has now turned into 9 cups of flour. So make sure to measure correctly.

Mixing Bowl
This recipe makes two loaves of bread, so you will want a fairly large mixing bowl. I recommend metal, but a big heavy ceramic bowl would probably work quite well.

Mixing Spoon
I use a wooden spoon. Your stainless steel spoon? It's going to bend. That $1 wooden spoon that came in a 3-pack? It's going to break. If you don't have a thick, sturdy wooden spoon already, go to the store where you buy your cooking supplies and pick up the plainest, thickest, most medieval-looking spoon you can find. They usually don't cost that much more than the spoons of lower quality, but they will probably last forever.

Oven
A decent oven is required for this. My oven is electric, the instructions I give later will work for gas as well. Wood fired ovens are great, and they work very nicely. You don't need a stone, wood-fired oven to make good artisan breads. I have had some good ones made in these ovens, but most of the best loaves I have had came from bakers who were passionate about bread, and used huge gas ovens. How your oven produces the heat is a very minor factor, as long as it can produce and hold the heat.

Baking Stone or Baking Sheet
A baking stone can turn a mediocre oven into a great one. They do an amazing job at holding heat and releasing it slowly to keep the oven at a consistent temperature. Ideally, you want to slide your bread directly onto a hot stone and let it bake there. This gives excellent oven spring (more on that later). If you're not ready to perform that maneuver it is nearly as good to slide a cheap metal pan with your loaves onto the stone to bake the bread.
Using a baking sheet without a stone is not quite as good, but I am sure good bread can be produced this way. If you don't have a stone, don't sweat it.

A surface to knead and shape the bread on
I use an old wooden bread board to shape my loaves on. Wood has a great quality of not sticking to dough too much, but just enough that you can use that to your advantage when shaping. Alternately, a wooden or stainless steel counter top can also be used to knead or shape bread.

Personally, I knead my bread in the same bowl I mix it in. It's largely a matter of personal taste, the technique I show later for mixing makes this the easiest way to do it for me.

Step 3: Feed the Starter

A sourdough starter is a relatively stable colony of yeasts and bacteria. Usually there will be several different species. The yeast provide the leavening (the gas) for the bread, the bacteria provide the acidity.

Each starter is different, and required different feeding cycles. Whatever you need to do to your starter to get it up to breadmaking activity, do it.
My starter is a rye flour starter and I usually have to only feed it once or twice before it is bubbling and ready.

If your starter has not been fed in awhile and you don't give it at least a feeding before making your levain, it might not be sufficiently active and your bread could turn out a bit flat. For me, this means taking it out of the refrigerator the evening before I am going to make the levain, feeding it, and going to bed. Next morning I feed it once again. Then that evening it is time to make the the levain.

Step 4: Mix Levain

Levain is French, describing a sourdough leavening agent. When I use levain here, I mean the leavening ingredient you add directly to the bread, as opposed to the starter, which is the sourdough culture.

To make a rye levain, combine:

1 cup of Rye Starter
1 cup of Rye Flour
1/2 cup of Water

Mix this all together in a container, cover it, and let it sit overnight (or 8-12 hours, depending on the temperature. A colder temperature means the microorganisms will metabolize the flower more slowly. Make sure your container is not too small, this mixture will slightly expand in size overnight.

Step 5: Baking Day: Build Levain

The levain should be smelling wonderfully like fermentation (or like an old, foot, it all depends on your starter).

Add 3 cups of water to the levain and mix together. Now add an additional 1/2 cup of rye flour and any whole grain flours you are using in the recipe. If you are using whole wheat flour, it goes in now. This is because whole grain flours absorb water more slowly than white flour. Since they are going to be absorbing that moisture anyway, you may as well have them do it now so your dough is less wet during kneading, making it easier to handle. If you are not using any whole wheat flour or extra rye (you really should, it adds a lot of flavor), just add a cup (leveled, always level!) of the bread flour you would be mixing in later to the mix now.

Stir this up and let it sit for 30-60 minutes, covered, at room temperature. At the end of this you should have a soupy mix.

Step 6: Mix, Autolyse, Knead

Mix
Combine all of the remaining flour in the recipe with the salt. DO NOT FORGET THE SALT. Bread has three ingredients, water, flour, and salt. You're unlikely to get very far without the flour or water, but the salt is fairly easy to forget.
In the mixing bowl, stir the flower and the salt together. Make a well in the center of the flour and pour in the levain. Use the wooden spoon to mix this together and integrate it as well as you can. Do not worry about mixing too hard, you should be mixing vigorously to combine the ingredients.

Autolyse
Autolyse can describe both an action and a period of time. You will autolyse your mixed dough, for an autolyse period (what?). All this means is cover the bowl with a damp cloth or plastic and let it sit for 10-15 minutes. This will allow the grains time to absorb the water, and will also assist with gluten development.

Knead
I do this in the bowl. Because the wet ingredients were poured into the well of flour, there is probably still flour coating the sides and bottom of the bowl. Alternately, the more common method of kneading dough is to lightly flour a wooden surface and knead on that.

You should knead the dough for 10-15 minutes.

To knead dough, first flour your hands, including between your fingers. Then press the dough out until it is flat, fold the edges inward, and press down again. You want to apply at much strength as possible to the dough, really beat it up. While you are doing this, you want to try to avoid the dough sticking to your hands or the surface you are kneading upon. The temptation will be of course to keep adding more flour to the board and your hands. Avoid this. This incorporates more flour into the bread, and it will make it too dry. Dry dough hinders gluten formation, and produces bread of inferior flavor that goes stale more quickly. When it comes to dough, wetter is better. The best way to avoid using too much flour is to keep the dough moving. Prolonged contact with the kneading surface or your hands will not occur if you are kneading fast and hard, frequently folding and moving the dough.
Having said this, since we hydrated the whole grains and allowed an autolyse period this dough should actually seem quite dry when you get to the kneading phase. The proportions mentioned here create a dough of moderate hydration.

Try this technique, take a leveled quarter cup of flour. Tell yourself that this is all the flour you will use to flour the board and your hands. Once you run out there is no more. This will help to resist the temptation to constantly add more flour.

Kneading is generally the most difficult skill to learn when it comes to bread baking. I could write a lengthy instructable on kneading technique alone. Baking books and a Youtube search will supply you with many techniques.

When the French describe kneading, they often say that one is "giving the dough strength". Kneading the dough has a few purposes. Kneading the dough makes the bread a very consistent mixture, it also incorporates air into the dough, which is good. The main purpose of kneading the dough is to develop gluten. Gluten gives dough its elasticity. This allows the dough to be shaped into the many traditional shapes that bread can take. More importantly, the elasticity of the gluten allows tiny pockets of gas to form in the bread. The carbon dioxide produced by the yeast are trapped in these small balloons instead of bubbling out of the surface. This is what allows bread to rise.

When you have finished kneading the dough it should be elastic and springy. If the dough seems too slack there is no harm in kneading even more, it is very difficult to over-knead bread when using your hands. When the dough seems right, fold the sides down together to form a ball.

Place the ball of dough in a large, lightly oiled bowl and cover with a damp cloth or plastic wrap.

Step 7: Primary Fermentation


At the end of the mixing and the kneading, let the covered bowl rest for 4 hours at room temperature. Bakers call this the primary fermentation. This period of time allows the yeast to start the fermentation process. They begin producing small amounts of carbon dioxide. Just as importantly, the bacteria in the sourdough culture also begin metabolizing and create the complex flavors of a sourdough loaf.

This is a great time to clean up the mess that was probably created in the mixing and kneading process. A quick soak is usually the best way to clean off your mixing bowl and spoon. Wipe down the counter top and floors, which may be dusty with flour. Then go do whatever you like for a few hours. Be aware that in warmer environments the yeast are more active. If you are baking bread on a summer day times for the primary and secondary fermentation will probably be different.


Step 8: Shape and Proof

Now, the dough has fermented for four hours. It will have expanded and will likely have a yeasty odor. This is good. Lightly flour the surface that you would like to use for shaping and move the dough from the bowl onto that surface. You will notice bubbles have formed and that the dough is quite loose and elastic.

Often, bakers will divide the dough and form it into a round pieces, called a preshape, and let it rest for awhile before they move to the final shaping phase. For a small amount of dough like this that step is unnecessary.

So, get a knife, divide your dough into two equal pieces and shape them into loaves. There are many different formed that can be created when hand shaping bread. The two pictures are the batard and the boule .

A batard is an elongated, vaugely football-shaped loaf of bread. It can be shaped by stretching the dough out, folding in the sides, and rolling it up into the batard shape. The two folds of bread that create the seam are pressed together against the shaping surface to fuse it shut. The batard is then placed seam-side down on a lightly floured baking tray.

A boule is the easiest shaping technique to learn. It is the simple round shape. One method to shaping is to fold the sides under and to push the middle outward as if you are feeding the edges of the dough into a sack. When the sack is getting full (if the surface tears it is too full!) the edges of the mouth of the sack are brought together. Traditionally, the seam-side is then placed down on a board and the loaf is quickly rotated. The slight sticking of the dough to the wood eventually fuses the seams together and the loaf is shaped. I have very large hands so I actually pinch the seam closed with a rotating motion using the palm of my hand.

There are two mistakes easily made when shaping a loaf of bread. The first is to degass the bread. The primary fermentation has built up all these lovely bubbles, do not force them out of the bread! Be as gentle as possible with the dough in this step because the gas suspended there will help to achieve a good rise during baking. The best way to avoid this is to not press down on the dough.
The second mistake is to lose tension of the dough during shaping. This is a bit difficult to explain but, imagine if you were wrapping a rubber cord around a pencil. You would get nowhere if you let go of it frequently to get a better position for winding. It is the same with shaping the loaf. When you have folded the dough and are getting ready to roll it up for a batard, do not let go of the dough! Keep a hand on it to maintain the tension or your loaf will sag and flow outward. It will end up being flat and very wide. A tightly-shaped loaf will remain tall and nearly identical to the form you create when shaping it.


In bakeries, baskets covered with floured linen are often used to allow the bread to "proof" or undergo the secondary fermentation. This object is called a couche and is very nice for certain purposes but unnecessary here.

What we will do is place the shaped loaves seam-side down onto a lightly floured baking pan. Make sure to allow a lot of space between the loaves, they are going to grow. Cover the loaves in floured plastic wrap, or another damp cloth. Keep them at room temperature and allow the loaves to rise for two hours. Try to disturb them as little as possible.

Note: When some people think of sourdough, they want a very sour taste to their bread. This recipe is not designed to have a very sour taste, but a very complex flavor. If you want to have an even tangier loaf there is an easy way to achieve this at this step. Wrap up your loaves very tightly and immediately put them in the refrigerator. Leave them there for 24 hours. When that time is up take them out and proceed with the instructions as normal.
Why this makes the dough more sour is that bacterial metabolisms operate better at lower temperatures than those of bread yeasts do. So, when you refrigerate the dough the yeast slows down to a crawl and the bacteria slows down to a slow walk. The bacteria in the culture are what produce the acidity so the yeast have been effectively put on hold while the bacteria have some time to produce the acids. When the dough comes back to room temperature the yeast start working faster than the bacteria again to produce gasses. However, the bacteria had the chance to produce all the tang that is the feature of some sourdough breads, but were able to do so without the bread overproofing.

Step 9: Score and Bake

Preheat the oven to 450 degrees Fahrenheit (or 230 degrees Celsius) . Make sure to give the oven sufficient time to preheat. Your oven might have a small light or indicator to let you know when the oven is preheated. I recommend you give at least another fifteen minutes after the light goes on for the oven to heat fully. The air inside the oven might be that hot, but your baking stone and the walls of the oven are not. As soon as the oven door is opened the temperature will drop rapidly. If the walls of the oven and the stone are fully heated, this can be minimized.

When the oven has fully heated, it is time to uncover and score the bread. Scoring the bread is the process of cutting the loaves with a knife or a razor before baking. Proper scoring can be done quite artfully to create a more appealing loaf of bread. The more practical purpose of scoring is to control the direction in which the bread expands. The surface of the bread bakes more quickly than the interior, so the top of the bread is often solidified while the middle is still expanding. A loaf that has not been scored can get a strange, lopsided, "blowout" look. Scoring helps to minimize this by giving the loaf fault points where it can easily split if it needs to. So the splitting occurs in a way that doesn't change the shape of the loaf in an unappealing way.

There are many different patterns of scoring that can be used on a loaf. I recommend the ones I have used here to get the best shape. For a longer loaf, make gashes that are mostly parallel to the longer part of the loaf. For a round loaf, use a pattern that will encourage the loaf to expand in all directions. The "tic tac toe" scoring pattern is easiest for this purpose.


When the loaves have been scored it is time to slide them into the oven. Place the baking sheet directly on the stone, if you are using one. If you have a large enough baking stone you can use a peel to slide your loaves directly onto the baking stone and bake them on it.

To get a good crust, baking with steam helps. You can put a metal tray full of water on a lower shelf. I throw about a cup of water onto the bottom of the oven as I'm closing the oven door. If you do this, make sure the light bulb in your oven is protected from splashes. Cool water on blazing hot glass is not a good idea.

Close the oven door and bake for 20 minutes. When this time has passed reduce the heat of your oven to 400 degrees Fahrenheit (200 Celsius) and bake for another 20 minutes. When that time is up your bread is done baking, remove it from the oven.

Place the bread somewhere to cool, I use a wire shelf. Many people speak of the great taste of hot bread. This is definitely true when it comes to home made dinner rolls and the like. However, if you were to eat a hot slice of this bread it will probably taste a bit bland.
The starches in the interior of the bread are still setting up and solidifying. You have to wait until this bread is completely cool to eat it. In fact, I would recommend waiting ten hours or so for the maximum flavor. Yes, this bread actually gets better with age!

Step 10: Eating and Storage


So, you have made this bread using all wild yeast and bacteria. These loaves have literally been days in the making, and now it is finally time to eat them. Make sure you appreciate them, invite a few friends over, make some high quality sandwiches, or just enjoy slices of this delicious, tangy bread. I recommend a serrated bread knife for cutting it.

My personal favorite use for this bread is a roast beef and horseradish sandwich. However, try a slice without anything on it. You might find that a good sourdough bread is flavorful enough to stand on its own.

Enjoy!



To store the bread it is possible to keep the crunchy crust if you wrap the loaf in cloth or in a tightly rolled up paper bag. The best way to extend the life of the bread is to keep it in a bread box or sealed container. This bread will last longer than other artisan breads because of the whole grains and acidity. It will take a lot longer to go stale but it will eventually dry out. Often I will leave a loaf out on a bread board for everyone to take slices from during the day. I place it cut-side down to prevent the interior from drying out.
If your bread does go stale before being eaten (a rarity for me) it makes excellent toast or croutons.


Step 11: Summary

Here is a summary of all the steps, and the ingredients, for quick reference.


Rye Levain
1 cup Rye Starter
1 cup Rye Flour
1/2 cup Water

Bread
All of Rye Levain
3 cups of Water
1/2 cup Rye Flour
7 1/2 cups Bread Flour
1 Tablespoon of Salt


Make levain, let age overnight.
Build levain, adding all remaining whole grains.
Mix and knead, 10-15 minutes.
Primary fermentation, 4 hours.
Divide and shape.
Secondary fermentation, 2 hours.
Bake at 400F/230C for 20 minutes
Reduce heat to 400F/200C and bake for 20 minutes.
Cool.
Eat.

Bread Contest

Runner Up in the
Bread Contest