Flour. Water. Salt. Starter. That sounds simple enough—until you discover there are approximately 4,327 opinions about which flour to use, whether your water is plotting against you, and exactly how much cheese a loaf can hold before it becomes a dairy delivery system.
Sourdough isn't just a recipe. It's a fermentation system.
Change the flour and you may change gluten development, fermentation speed, flavor and hydration.
Change the water and you change dough consistency.
Change the salt and you can affect flavor, dough strength and fermentation.
Then we start adding cheese, olives, garlic, cinnamon, fruit, nuts, chocolate and everything else we can reasonably convince a loaf of bread to carry.
This guide is the home of the Squirrelly Girl Sourdough Ingredient Encyclopedia— a growing collection explaining what individual ingredients do, how to use them and what happens when you change them.
Before worrying about jalapeños, chocolate chunks or the heroic quantity of cheddar you're contemplating, understand the four ingredients doing most of the work.
Flour provides starches for fermentation and the proteins responsible for developing the gluten structure that helps bread hold gas and rise.
Water hydrates flour and determines much of your dough's consistency. Both the amount and characteristics of your water can influence how your dough feels and behaves.
Salt does far more than provide flavor. It also influences dough strength and fermentation, making it one of the smallest ingredients with one of the biggest jobs.
Your starter brings the living culture responsible for fermentation. A strong, active starter gives your dough its foundation before the rest of the ingredients get involved.
Need help understanding your starter? Start with the Squirrelly Girl Sourdough Academy.
Explore Sourdough Academy →Flour deserves its own section because switching flour can completely change your dough.
Bread flour, all-purpose flour, whole wheat, rye and heritage grains don't behave exactly the same way. Protein level, bran, mineral content and water absorption can all influence the final loaf.
The first expansion of this Ingredient Encyclopedia will be our Sourdough Flour Guide, followed by individual guides answering the most common sourdough flour questions.
A practical comparison of common flours and how to choose one based on the bread you want to bake.
Guide Coming SoonWhy bread flour is commonly used and what its protein content can mean for dough strength and structure.
Guide Coming SoonYes, you can make sourdough with all-purpose flour. Learn where it works well and what differences to expect.
Guide Coming SoonWhole wheat brings additional flavor and nutrition while changing water absorption and dough behavior.
Guide Coming SoonRye can bring incredible flavor and fermentation activity to sourdough, but it behaves differently from wheat flour.
Guide Coming SoonHeritage grains bring distinctive flavor and baking characteristics that deserve more attention.
Guide Coming SoonWater looks like the boring ingredient right up until your dough becomes soup and you begin questioning every decision you've made.
Water quantity determines hydration, while temperature can affect dough temperature and fermentation speed. Water quality can also matter when you're maintaining a sourdough culture.
Tap, filtered, bottled or something else? We'll break down what actually matters.
Guide Coming SoonLearn why water temperature can be useful for managing dough temperature and fermentation.
Guide Coming SoonButter, olive oil and other fats can change tenderness, crust, richness and handling. They can turn rustic sourdough into something softer and richer.
Why olive oil appears in focaccia, sandwich breads and other softer sourdough recipes.
Guide Coming SoonButter adds richness and tenderness while changing the texture and character of the finished bread.
Guide Coming SoonHoney, sugar, maple syrup and other sweeteners aren't only about making bread taste sweeter. Depending on the recipe and quantity, they can also influence browning, softness and fermentation.
Why bakers add honey and how it can influence sweetness, browning and texture.
Guide Coming SoonWhat sugar does in enriched sourdough breads and when you actually need it.
Guide Coming SoonHow liquid sweeteners can be incorporated without accidentally turning your dough into pancake batter.
Guide Coming SoonUseful in sweeter loaves and desserts where deeper caramel flavor is part of the plan.
Guide Coming SoonMilk, cream, butter and eggs take sourdough into enriched-dough territory and can create softer, richer breads, rolls and desserts.
What happens when some or all of the water in a sourdough recipe is replaced with milk.
Guide Coming SoonHow eggs contribute richness, structure and color to enriched sourdough recipes.
Guide Coming SoonThis is where normal bread starts getting ideas.
Cheese, garlic, olives, peppers and herbs can transform basic sourdough into an entirely different loaf. But inclusions also introduce moisture, oils, salt and weight that your dough has to deal with.
Cheddar, Parmesan and other cheeses can produce incredible loaves when you understand how much to add and when to add it.
Cheese Guide Coming SoonRoasted garlic and fresh garlic behave differently. We'll explain how to use both successfully.
Garlic Guide Coming SoonOlives bring salt, moisture and enormous flavor—three things your dough will definitely notice.
Olive Guide Coming SoonJalapeños, chili peppers and dried peppers can add heat without turning the loaf into chaos.
Pepper Guide Coming SoonRosemary, oregano, thyme and other herbs can be used alone or paired with savory inclusions.
Herb Guide Coming SoonFresh, roasted, caramelized and dried onion each bring different amounts of moisture and flavor.
Onion Guide Coming SoonSeeds and grains can add texture, flavor and visual appeal inside a loaf or across the crust.
Inside the dough, outside the loaf—or both.
Guide Coming SoonFlax absorbs water, which is worth knowing before casually dumping half a bag into your dough.
Guide Coming SoonA simple way to add crunch, flavor and substance to sourdough bread.
Guide Coming SoonRolled oats, soaked oats and oat toppings can each be used differently.
Guide Coming SoonDried fruit and nuts are sourdough classics. The trick is getting plenty into the loaf without destroying the dough structure you spent all afternoon developing.
A classic inclusion for cinnamon-raisin and breakfast-style sourdough loaves.
Guide Coming SoonTart, sweet and especially useful when paired with nuts or cheese.
Guide Coming SoonA traditional addition that pairs especially well with fruit and whole-grain breads.
Guide Coming SoonIdeal for sweeter sourdough breads, cinnamon loaves and dessert-style baking.
Guide Coming SoonNobody said sourdough had to behave itself.
Chocolate, cocoa, cinnamon and other sweet additions can turn fermented dough into everything from breakfast bread to full-blown dessert.
How much chocolate a sourdough loaf can reasonably carry is an important scientific question we intend to investigate thoroughly.
Guide Coming SoonCocoa changes more than color and flavor, so chocolate dough often needs different handling.
Guide Coming SoonFrom cinnamon swirls to inclusions, there are several ways to use it depending on the loaf you're making.
Guide Coming SoonUseful when sourdough crosses over from bread basket to dessert table.
Guide Coming SoonSome of the most useful sourdough questions aren't about what an ingredient does. They're about what happens when you don't have it.
This part of the Ingredient Encyclopedia will answer practical questions including:
As these guides are published, this section will become the shortcut for bakers standing in front of their pantry saying, "Well... I don't have that."
The Ingredient Encyclopedia will also explain the relationships between ingredients instead of simply telling you which ones to put in a bowl.
Why protein percentage matters and why higher isn't automatically better for every loaf.
How ingredients influence the network responsible for trapping fermentation gases.
Understanding how flour and added ingredients absorb or contribute water.
How ingredient choices can influence the speed and behavior of fermentation.
Sometimes the flour isn't the villain.
If your starter isn't rising, bubbling or behaving normally, changing every ingredient in your bread recipe probably isn't going to fix the underlying problem.
Start with our dedicated troubleshooting hub and figure out what your starter is trying to tell you.
Troubleshoot Your Sourdough Starter →Ingredients make much more sense when you understand the fermentation system they're joining. Continue learning with these Squirrelly Girl guides.
You can experiment with flour, hydration, salt, cheese, chocolate and every other ingredient in the pantry.
But every great sourdough loaf still starts with one very important ingredient: an active sourdough starter.
Squirrelly Girl Sourdough Starter is a live sourdough culture from a real working micro bakery, used in daily baking since 2018.
The Squirrelly Girl Sourdough Ingredient Encyclopedia will continue growing as new ingredient guides, comparisons and substitution answers are added.
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Bake or Get Covered: If your starter fails to activate into a bubbly, active, bake-ready culture.
We’ll either send you a fresh replacement batch completely free or issue a 100% refund.
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