Sourdough hydration is a topic that baffles many a home baker, and for good reason: hydration is the foundation of every sourdough recipe, whether we realize it or not.
Because sourdough hydration is calculated using a math formula, many people get overwhelmed by the concept, but it’s nothing to be afraid of. The hydration of your sourdough affects everything, from the length of time it needs to ferment, to the ease of shaping, to the oven spring in the oven, to the crumb inside the loaf. Finding the right hydration for you is critical. In this post, you’ll find answers to many common hydration questions, troubleshooting tips, and more.
In every sourdough recipe, there are certain variables that you can adjust to suit your kitchen, your ingredients, and your life. I call these Leavenly Moments, and they are times where you can make changes and experiment. Dough hydration is a Leavenly Moment: you can adjust it higher or lower depending on your preference. If you’re making sourdough from a recipe that makes an 85% hydration dough, but you know that you prefer to make a 75% hydration dough, you can make this change while following the remainder of the recipe verbatim. The power is in your hands!
What is Hydration?
You may have seen recipes for “75% hydration sourdough”, or posts on social media highlighting a beautiful loaf of sourdough bread that is “85% hydration”… But what exactly does that mean?
Hydration is the term used to describe how much water is in a sourdough bread recipe. It’s based on a simple math formula that takes into account how much flour and how much water is in the dough. Hydration is expressed as a percentage because of baker’s percentage.
Without going into too much detail, baker’s percentage takes into account the amount of the ingredients in a recipe compared to the amount of flour. It’s a quick and easy way for a baker to recognize if the ratios in their recipe are correct, and to be able to scale the recipe up or down easily. Salt, for example, is typically in the 2 – 2.2% range in a sourdough recipe. With my Simple Sourdough Recipe, I know both the amounts in grams and the percentages by heart. This is simply because I’ve made it dozens and dozens of times and I have it committed to memory. It’s 100% flour, 75% water, 20% leaven, and 2.2% salt. Baker’s percentage means you can figure out the amount of each ingredient in grams so you can make one loaf, three loaves, or fifty loaves.
So, hydration is essentially the baker’s percentage for the water in the recipe. My recipe above is 75% hydration, which means there’s 750g water per 1000g flour.
Why does hydration matter?
Sourdough hydration has a huge effect on dough and the finished bread. It influences many variables, such as shaping, oven spring, crumb and texture, but the single most important thing hydration influences is fermentation.
I hear from beginner bakers all the time who are struggling with sticky dough that’s impossible to shape, dough that spreads into a pancake once scored, and flat loaves out of the oven. So many people struggle with this one aspect of sourdough baking, and I was one of them! So I can completely empathize.
The key piece to remember is this: the higher the hydration, the faster the fermentation. This means if your dough is 85% hydration, it will ferment faster than a dough that’s 75% hydration. Fermentation happens faster in the presence of more water. So, when people write to me wondering why their dough is acting this way, I recommend cutting back on the bulk fermentation time, and it always does the trick.
If you’re struggling with dough that’s impossible to shape, or pancake-flat dough, or loaves with no oven spring, I recommend the same to you: cut 30-60 minutes from the bulk fermentation time, at the end of the bulk rest. Always take notes as you make changes, so you can replicate the successes!
What happens to dough if hydration changes?
Increasing hydration means there is more water in the dough. More water means faster fermentation, which means many high-hydration doughs are overfermented. See Why Does Hydration Matter?, above, for more details on this and how to solve this problem.
Decreasing hydration results in a dough that is much easier to handle, and therefore is very beginner-friendly. I usually recommend that brand-new sourdough bakers start around 70% hydration, get a feel for the dough and experience watching it change as it ferments, and then slowly increasing hydration to a manageable level. My own personal favorite is 75%, so it’s not as though higher hydration is something to shoot for. If you’re making amazing, delicious bread at 70% or 75%, then stick with it! Higher hydration is not the goal; baking good bread with consistent results is.
How do I know if my dough is the right hydration?
There is no “right hydration” – there’s just the hydration that works best for you. For example, I used to always bake 85% hydration loaves. I couldn’t figure out why my dough was so sticky and hard to shape, and why my bread always came out flat. It wasn’t until I experimented with lowering the hydration that my loaves had great oven spring, and shaping became a piece of cake. My perfect hydration is 75%, and that’s based on my experience level, my ingredients, and my altitude (I live at 5,700 feet).
The great thing about sourdough is that it’s easy – and inexpensive! – to experiment with different variables. One of those variables is hydration, so play with it. Take notes each time you bake, so you can remember what to do when things go right.
What problems can hydration cause?
A high hydration dough can result in a sticky mess when shaping, a flat disc after scoring, and a low-profile finished loaf. This is all likely due to overfermentation.
A low hydration dough can resist added ingredients, as it is a bit more stiff and firm. Mixing in seeds, for example, would be much easier with a higher hydration dough than a lower hydration dough. That’s not to say it’s impossible to mix ingredients into a lower hydration dough, but you will find it resists it more. A low hydration dough can also result in a tighter crumb, which is preferable if used for toast, sandwiches, etc; however, some bakers like the open crumb that accompanies a high hydration dough.
Do different flours affect hydration?
Yes – the kind of flour you use in your dough will affect the hydration level. White flours don’t absorb as much liquid as whole wheat and whole grain flours. For example, most whole wheat sourdough recipes have a hydration level of 10-15% higher than white flour sourdough recipes.
If you’re using a blend of flours, it depends on the ratio of white to wheat flours. I use 100g whole wheat flour and 900g bread flour, but if I were to increase the amount of whole wheat flour and decrease the amount of bread flour, I would see (and feel!) a noticeable difference in my dough: it would be more stiff and firm because the higher amount of whole wheat flour would have absorbed a lot more of the water.
Like high hydration, baking with high amounts of whole wheat flour is something that comes after gaining experience, as it can be unpredictable and unruly. I recommend having several bakes under your belt before playing with increasing your whole wheat flour amounts.
What hydration is my dough?
Below, you can utilize Leavenly’s Hydration Calculator to determine the hydration of your dough. It’s also important to have a basic concept of how to calculate it yourself.
Hydration is the total amount of water divided by the total amount of flour, times one hundred:
So if your recipe calls for 800 grams of water and 1000 grams of flour, your calculation would be:
Some folks like to calculate their hydration including their leaven, as it does change the final result. However, it’s so negligible that I recommend simply using flour and water. (For example, using the same equation above, including 200 grams of a 100% hydration leaven results in a dough hydration of 82% – a difference of only 2%.) That said, there is an option in the Hydration Calculator below for calculating the hydration of your dough accounting for the hydration of your leaven.
To use the Simple Sourdough Hydration Calculator, type in the amount of flour and the amount of water in your recipe. If you’re also using another liquid like milk, you can enter it under “Other Liquid”. The hydration percentage will auto-populate. Simple!
To use the Detailed Sourdough Hydration Calculator, type in the amount of flour, water, other liquid (i.e., milk), leaven, and the hydration of your leaven. The hydration percentage will auto-populate.
Note: If you’re not sure what the hydration of your leaven is, you can utilize the Simple Sourdough Hydration Calculator to figure it out!
Can I change the hydration level in my dough?
Yes, and I encourage you to play with it! As above, make sure you’re taking notes when you play with hydration levels so you can replicate your successes.
To start, begin by using the Hydration Calculator above to determine what hydration your dough is. If it’s 80% or higher, try decreasing your water so you can try a 70% or a 75% hydration dough. Conversely, if your dough is 75% or lower, give a higher hydration dough a try. Add more water until you achieve an 80% to 85% hydration, and see what happens.
You may be thrilled by the results you get from these changes, or you may be disappointed. But either way, experimenting with hydration is going to make you a better baker and give you good experience handling different types of doughs. And since sourdough costs mere pennies per loaf to make, it’s an inexpensive way to gain knowledge and experience!
Which hydration should I choose?
The answer to this question really depends on your experience level, and what you’re looking for in your sourdough. It’s fun to play with hydration levels and find that perfect Goldilocks level, but if you’re seeking something in particular from your bread, hydration level will make a difference.
If you want easier shaping, slower fermentation, and better oven spring, opt for a lower hydration, between 70-75%. Conversely, if you want a more open crumb and thinner crust, try a higher hydration dough between 80-85%.
And finally… Don’t be afraid to experiment!
I tend to say this until I’m blue in the face, but there’s nothing to be afraid of when it comes to experimenting with your sourdough. The worst possible outcome is that you’ll have an ugly bread that’s still delicious. If it’s really atrocious, turn it into croutons or blend it into sourdough bread crumbs!
Seriously, experimenting with your dough will give you hands-on experience that is far more valuable than anything I or anyone else could tell you about hydration. You need to just play with it and feel the differences for yourself. So what are you waiting for? Go play with your sourdough!