Ingredients

Frequently Asked Questions

The basic ingredients of sourdough bread are: 

  1. Flour
  2. Water
  3. Salt
  4. Sourdough Starter

Flour – Always use a high protein “bread flour,” which is referred to as “strong flour” outside the US.  You want a flour formulated for bread with at least 12% protein.  Bread flours are not the same as “whole wheat” or “whole meal” flours which may also be high protein, but they contain the whole wheat berry (bran, germ and endosperm) and will produce a more dense loaf.  Bread flour is typically sifted to remove some of the bran and germ.

Water – Always use unchlorinated water when making bread. 

Salt – Any type of non-iodized salt will work with sourdough bread. 

Sourdough Starter – Sourdough bread is made with a wild yeast sourdough starter, not commercial baker’s yeast.  Some recipes are “hybrids” which include sourdough starter and commercial yeast, but sourdough purists only consider true sourdough to be naturally leavened bread with no commercial yeast added. 

A wheat kernel consists of three parts: bran, germ, and endosperm. Highly refined flour have all of the bran and germ removed and are largely contain only endosperm.  This is the fine, soft, white fluffy content of flour.  The extraction level of flour generally refers to the percentage of whole flour (bran+germ+endosperm) that remains in the bag of flour after processing.  100% extraction flour means that noting has been removed.  This is the same as whole grain or whole meal flour.  85% extraction means that 15% of the coarse material has been sifted out and 85% of the whole flour remains.

“High-extraction” flours are sifted flours that include more bran and germ than typical “refined flours.”  High extraction flour are more akin to a blend of refined flour and whole-wheat flour.

Extraction rates over 80% are usually considered to be “high-extraction.”  Refined bread flours typically have an extraction rate of about 72-75% and whole wheat is 100% extraction.  So, 85% is about the midpoint between these two extremes.  

An extraction rate of 80-85% means that unlike highly refined white flours, these flours include some of the bran and germ that you would typically find in whole wheat.  

A high-extraction flour is very similar to a blend of white bread flour and whole wheat flour.  A rough approximation would be 80% white bread flour and 20% whole wheat flour.  

High-extraction flours are increasing in popularity and are sometimes called “artisan bread flour.”

Bread flours are a matter of personal preference, but for beginners I recommend using a white bread flour with 12-13% protein.  Most supermarket bread flours, like King Arthur Bread Flour in the U.S., are in this range. 

Many recipes also recommend blending in 10-20% whole wheat flour with a high-protein bread flour.   

Some flours list the “Ash %.”  The Ash % is a way to determine, in a laboratory, how much bran has been removed from the flour.  Refined flours typically have a low ash percentage and whole-grain flours generally have a high ash percentage (because they contain more bran fibers).  

For example, whole wheat flour typically has an Ash % of 1.4%.  Refined, all-purpose flour has an Ash % of .55%.   By looking at the Ash % you can determine how much bran or whole wheat particles are in the flour.  

Because there is not a standard definition of “bread flour” (at least in the U.S.), it is helpful to read the Ash % to determine how much whole grain remains in the flour.  A bread flour with a low ash percentage (e.g., .55%) contains very little whole grain, and a bread flour with a high ash percentage (e.g., .80%) is similar to a blend of bread flour and whole wheat flour. 

The ash percentage is also somewhat correlated with the “extraction percentage” but there is no direct linkage.  

You can make sourdough with all-purpose or “plain” flour, but you will get better results with higher protein flours like “bread flour” or “strong flour” which typically have about 12.5% protein.  All-purpose flours have about 11% (or lower) protein. 

Most sourdough recipes are also formulated for stronger flours (12.5% protein), so when using all-purpose flours, sometimes the hydration recommended in the recipe is too much for all-purpose flours to handle.  For example, if a recipe calls for 75% water and bread flour, you may want to reduce it to 70% water for all-purpose.  

Also, try blending in up to 20% whole wheat flour with your all-purpose flour to add some additional flavor to the loaf. 

Not necessarily.  The protein level alone is not always an indication of a good flour for sourdough bread.  Here are some examples: 

    1. Whole-wheat, or wholemeal flour can have very high protein content (13% or higher) but using 100% whole wheat flour for sourdough baking will not produce a light, airy loaf.  It will be more dense than you may expect.  Most sourdough bread recipes are formulated for only a small percentage (less than 20%) whole wheat. 
  1. High protein flours create a more chewy crumb.  As the protein content of your flour exceeds 13%, the crumb will become more tough and chewy.  Very high protein flours (14%+) are very noticeably chewy.  Some people do not prefer this toughness in their crumb. If you prefer a more tender crumb, keep your protein content around 13%. 
  2. Some high protein flours do not produce strong gluten.  Flours like einkorn, emmer and spelt can be very high protein flours, but they do not have good gluten forming properties and do not produce great looking loaves when used at 100%.  Sometimes it is better to blend these flours in with a strong bread flour.  

Higher protein flours and more whole wheat content will absorb more water.  These are known as “thirsty” flours.  Sometimes you may need to adjust the hydration of a recipe and add a little more water if your dough seems dry when initially mixing.  Be careful, even 30-50g of additional water can go a long way. 

“High-extraction” flours and flours with high “Ash %” are an indication of the amount of wheat bran in the flour.  The bran acts like a sponge and soaks up water.   When using high-extraction or high ash flours (>1% ash), you may want to add a small amount of additional water. 

Yes!  Flour blending is part of the art of sourdough baking. Experience bakers create their own flour blends to produce a certain style, texture and flavor of a loaf. Some recommendations for flour blending considerations: 

  1. Blend high and low protein flours but try to keep your average protein % above 12%
  2. Blend mild refined flours with bold whole-wheat or stone-ground flours to pump up the flavor of a basic bread flour or all-purpose flour. 
  3. Add ancient grains (emmer, einkorn, spelt) in small quantities (up to 20%) to add different flavors to a basic bread flour. 
  4. Blend whole wheat flours with basic bread flour to produce a wheat-forward flavor but still produce a light airy crumb and a tall loaf. 

For beginners, I recommend using good quality supermarket bread flour or strong flour with at least 12.5% protein.  These are good basic flours to practice with as you develop your mixing, fermenting, shaping and baking skills.  You can combine up to 20% whole wheat with basic bread flour and most recipes will still work. 

When you have mastered these skills, begin experimenting with different types and brands of bread flour. Try locally milled flours, or mill your own.  Fresh-milled flour can behave quite differently than commercial flour, and it requires some experience to develop the techniques to work with these flours. 

If you are baking in large quantities, seek out local restaurant supply stores or wholesalers to purchase your flour in bulk.  

“Tap water” may include:

  1. Municipal water treated with chlorine
  2. Municipal water treated with chloramine
  3. Well water
  4. Reverse Osmosis Well Water
  5. Mountain spring water
  6. Filtered water
  7. Water with high sulfur content
  8. etc.

The best water for use in breadmaking is any type of unchlorinated water.  Water treated with chlorine can be filtered through most household water filters.  Water treated with chloramine (a combination of chlorine and ammonia) may need different types of filtration.  Check with your municipality for specific recommendations on filtering methods.  

Some recipes call for using warm water to jump-start the fermentation process, or to target an initial mixed dough temperature (Desired Dough Temperature).  

I do not advise adding water which would raise the starter or dough temperature above 87F/30.5C.  Once the starter or dough temperature exceeds this level, the starter and/or dough becomes very acidic and starts breaking down the gluten.  This is really a challenging situation, particularly for bakers in warm kitchens or tropical climates.  

When raising your dough temperature by adding water, always be careful not to exceed this threshold.  

At water temperatures of 140F/54C, you will kill off the yeast and bacteria.  

I typically use fine sea salt, but any type of non-iodized salt will work.  Some people prefer the flavor of specialty salts like pink Himalayan salt, for example, but my palate does not discern a difference.   

Always weigh your salt in grams because different types of salt have different weights by volume.  

This is a complicated question to answer.  Most bakers agree that you will bring out more sourness with longer, cooler fermentation times.  Many bakers achieve this by using less starter, which may seem counterintuitive, but it does slow down the fermentation process, and results in a more sour loaf.  

However, in my experience, the type of flour used also significantly impacts the “sourness” of the loaf.  For example, I believe what many people believe to be the classic “sourdough flavor” is actually the flavor of fermented rye flour. 

Try adding a little rye flour (10%) to your flour blend and see if you notice a difference.  Also try increasing the amount or type of whole wheat flour in your blend.  

More to follow on this important topic in the future. 

Most recipes recommend adding add-ins or inclusions (cheese, herbs, nuts, seeds) after the second round of stretch and folds (assuming you are doing four or more rounds).  This gives you a few rounds to incorporate the ingredients.  

Important: Certain types of add-ins can impact fermentation times!  Garlic and salt will slow down fermentation (note: nuts, cheese, and olives contain lots of salt).  When adding salty add-ins, I try to wait as long as possible. 

In some cases, I’ll laminate the add-ins into the dough during preshaping.  In other cases, I’ll add them during the last stretch-and-fold.  By adding salty or garlicky add-ins later it has less of an impact on the fermentation times. 

Also, if you are adding inclusions that contain oils, such as cheese or olives, the oils will produce a more closed crumb and a softer crust and crumb.  The oils can also accumulate under the loaf as it is baking and burn the bottom of the loaf.  

videos

Experimenting with Bread Flours

What is “bread flour” and how does it impact your loaves? 

In this in-depth video, Tom explores the mysteries of wheat, flour and bread flours.  He bakes 6 loaves of bread using six new types of bread flour and evaluates the differences in crust, crumb, color, flavor and fermentation rates. 

This video is jam-packed with new content never before seen in sourdough videos!

Tartine Bread: Beginner Mistakes and Tips using the Tartine Method

Is it possible for a beginner to make great sourdough bread? 

This 5-part series is the perfect starting point for beginning sourdough bread bakers. In this series, Tom demonstrates virtually every step of the process following the popular Tartine Country Bread recipe.   This video is also helpful for those trying the Tartine recipe for the first time. 

Additional resources

Where to Buy Flour Online From Smaller Mills (U.S.) – Food and Wine – A list of smaller flour mills in the U.S.  

A Flour Treatise, The Artisan – Everything you wanted to know about flours around the world.  

Flour Ash, What is it?, Bay State Milling – A helpful article on understanding the “ash” content of flour. 

Italian Flour: Types and Terminology – Bread, Cakes and Ale – A helpful article describing Italian flour classifications.