18 Ways to Make Sourdough Bread More (or Less) Sour

Back in the day, my family and I were used to store bought bread. And sourdough bread at the time was just…..well….too sour! But as time has gone on, I have started to enjoy more and more sour a flavor of bread. My children of course feel differently. They enjoy a much milder flavor, and they don’t shy away from letting me know!

I wanted my whole family to enjoy the goodness of sourdough bread, so I had to learn to adjust its sourness so that we could all enjoy the taste. That meant super sour for me and my husband, and mellow and mild for my kids.

So, how do you make sourdough bread more sour? The types of acids found in sourdough determine the flavor of the bread. There are two main types of acids found in sourdough bread, which give opposite flavors.

  1. Lactic acid – This type of acid gives a mild yoghurt like flavor.
  2. Acetic acid – This type of acid gives a sour vinegar like flavor.

Increasing the amount of acetic acid in sourdough bread increases the sourness of the loaf.

The beauty of baking sourdough bread at home is that there are ways you can adjust the sourness to produce a loaf that has the perfect sourness for you.

How to Adjust the Sourness of Sourdough Bread

From what you do with your starter, to how you proof the shaped loaf before baking, there are all sorts of tricks bakers use to manipulate the flavor of the bread. The trick to getting a more sour flavour is to find ways to naturally increase the amount of acetic acid in the bread.

I’ve played around with my classic sourdough bread recipes in many different ways to manipulate its sourness, and here I’ve listed 18 of my most effective ways to make sourdough bread more sour. If you like your sourdough bread mild, just do the direct opposite. There’s a handy table at the bottom of the article with a summary of what you can do at different stages of the bread making process, to manipulate the sourness of your sourdough bread.

1. Whole Grain Flour Makes Sourdough Bread More Sour

The flour you use in sourdough bread makes a big difference to how sour the bread becomes. Switching completely to whole grain flour will increase the sourness by a long stretch, even if you changed nothing else.

This is because whole grains contain complex carbohydrates, which encourages more of the acetic acid producing bacteria than white flour. For more information about how to use different flours in sourdough bread, check out my “Guide to Using Different Flours in Sourdough Bread”.

QUICK TIP: Whole grain flour will give you a more dense loaf, so play around with the ratio of white to whole grain flour in your loaf until you come up with a balance of density and sourness you are happy with.

2. Ferment Sourdough for a Longer Time to Increase Sourness

The longer your dough ferments (rises), the more sour the flavor. So if you want a really sour bread, take your time! As the dough ferments, it eats up sugars and starches in the flour. This takes away the sweeter notes of the flour, giving an increase in sour flavor. Some bakers will ferment their dough over 2 to 3 days to get that sourness! (For more information about how to use temperature to control fermentation, have a read my article “Full Guide on Using the Best Temperature to Proof Sourdough”

Note: If you are eating sourdough for its health benefits, be sure that the dough has had a minimum of 6 to 8 hours of fermentation time in total, as this will mean the whole dough has had time to ferment. Doing this will give you real sourdough bread at its mildest flavor profile.

3. For a Truly Sour Sourdough, Don’t Enrich the Recipe

Enriched sourdough loaves, are loaves with added ingredients such as butter, oil, milk, etc. The added fats in these ingredients soften the texture of the bread and reduce the sourness in the taste, giving a milder flavor profile. If you are after a really sour bread, don’t use any additional ingredients, especially fats like butter or milk.

Traditional sourdough bread only contains flour, water and salt. Keep your recipe simple to get a more sour flavor profile.

4. Add Rye Flour to Sourdough for a More Sour Flavor

Rye Flour, especially whole rye, contains a very unique set of enzymes and complex carbohydrates. When rye is used in sourdough bread, it helps to produce a unique set of sugars which encourage a higher amount of acetic acid production.

Rye flour is like a superfood to sourdough starter. It’s easily digestible and rich in nutrients, which is why it is commonly used to get sourdough starters going when they are new.

Many artisan bakeries use a 100% rye starter for all their sourdough breads, as it is super active and gives superior rising qualities and a good sour flavor.

FUN FACT: Rye flour is not very popular in commercially yeasted breads. Because of its unique characteristics, it gives the bread a gluey texture.

5. How Often Sourdough Starter is Fed will Affect how Sour the Bread Tastes

Feeding your starter more often gives it a milder flavor. The longer sourdough starter goes without food, the more acetic acid and/or hooch it develops. And this creates a more sour flavor.

Try switching to a more scarce feeding routine to give your starter a more sour flavor. Be careful not to be too scarce though, you don’t want it to starve and give you no bread at all!

Feeding a mature sourdough starter once every two days will still keep your starter active, but give it a good sour kick.

6. Keep the Hooch to Get a More Sour Loaf

Many bakers throw out the hooch that develops on top of sourdough starter. This brownish liquid, that develops when the starter has run out of food is full of sour flavors. Mix it right back into the starter during feedings to give your bread an extra sour flavor.

7. Extra Oxygen Encourages A More Sour Sourdough Starter

Giving your sourdough starter a really vigorous mix during feedings will help increase its oxygen intake. Oxygen encourages acetic acid development, which helps encourage a more sour flavor in your bread.

8. A Mature Sourdough Starter is More Sour Than a Young One

If you have made a starter from scratch, it doesn’t fully mature and develop its full depth of flavor until a good few months down the line. A more mature sourdough starter will give a more sour flavor. So be patient, and give your starter time to mature.

9. Fermenting at a Cooler Temperature will Give Sourdough Bread a More Sour Flavor Profile

Temperature is one of the easiest ways to adjust the flavor of your sourdough bread. Remember, the longer your dough ferments, the more sour the flavor will be. So one way of fermenting for longer is to slow down the fermentation rate by cooling down the temperature of the dough.

Try partially or even fully fermenting your dough in the fridge for a really sour flavor profile.

10. Feeding Sourdough Starter After its Peak will result in a More Sour Flavor

The point at which you feed your starter will affect how sour it is. For a more sour starter, feed your starter several hours after it has peaked. This will give the starter enough time to produce more of the acid producing bacteria that makes your starter sour.

If you like a more mild flavor, it is best to feed it just before it peaks. For more detailed information about when to use sourdough starter, have a read of my guide, “When to Use Sourdough Starter at its Peak to Bake Good Bread”.

QUICK TIP: This is also the same for any preferment you use for your recipe. If you wait until it passes its peak, you will end up with a more sour bread. Use it nice and early if you like a more milder flavor.

11. Water Temperature Affects Sourness of Sourdough Bread

Did you know the temperature of your water also makes a difference to the flavor of the bread? The reason why many bread recipes call for warm water is not only to get the yeasts and bacteria going. It actually also encourages a more sour flavor too. Use water that is around 90 F (32 C) for a more sour tasting bread.

Cooler water temperatures of around 80 F (27 C) will give you a milder flavored sourdough.

CAUTION: Don’t use water that is hotter than what you can comfortably touch. This will kill your starter!

12. Using Smaller Amounts of Starter in the Recipe will make your Bread More Sour

Another way of manipulating the sourness of your dough is to play around with the amount of starter you use. The smaller the amount of starter in the recipe, the more sour the flavor will be. This is because the starter will go through its food source at a slower rate and produce more acetic acid along the way.

Using a large amount of starter will mean that the bread can ferment quickly. It won’t have had enough time to produce as much acetic acid. There will be more lactic acid in the dough, giving a milder yoghurt like flavor.

13. Baking Soda Neutralises the Sour Flavor in Sourdough Bread

Adding baking soda to the dough gives it boosted rising power, but because it’s such a strong alkaline, it neutralizes the acids in the sourdough, which also neutralizes the sour flavor.

QUICK TIP: Adding baking soda to your dough just before shaping will help it rise further. This is a good way of getting a milder flavor in whole grain breads without compromising on the rise of your bread as much.

14. Degassing Sourdough Helps Increase Sourness

Degassing your dough every now and then (by moving it around, stretching it, etc.) helps to increase its sourness. It works by helping the bacteria find new pockets of sugars to feed on. This helps the dough to:

  1. decrease the amount of sugars and starches in the dough, hence increasing its sourness.
  2. ferment for a longer period of time, as the dough has a chance to rise all over again after being degassed.

15. Extending the Final Rise Increases the Sourness of Sourdough Bread

The final rise is another time to prolong that fermentation process. Once shaped, leave the loaf in the refrigerator, or in a cooler spot to slow down the 2nd rise for as long as possible. This will increase its sourness even further.

16. Using a Stiff Sourdough Starter Results in a More Sour Loaf

Making a starter with a reduced hydration level actually affects its flavor. A starter that is very wet will be encouraged to produced more lactic acid, which gives your dough a more mild yogurt like flavor.

But a starter that is dry will produce more acetic acid, giving it a more sour flavor. Play around with the hydration level of your sourdough starter to adjust its sourness until it gives you flavors you love.

QUICK TIP: Remember to adjust your recipe according to the adjusted hydration of your starter. i.e. if you have used less water in your starter, you may need to add extra water to your recipe.

17. Using a Preferment Helps Increase Acidity in Sourdough Bread

A preferment is simply a stepping stone between the starter and the dough. It consists of feeding a little bit of starter, to a larger amount of flour. A few hours later, this preferment is then used as a starter for the sourdough recipe, rather than the starter itself.

Using a preferment for your dough not only increases its rising power, but also increases its acidity levels, which increases the sour flavor in the bread.

18. Relocate to Give Homemade Sourdough Bread a Better Flavor

Now…it depends how obsessed you are with getting that sour flavor, but where you live makes a difference to the taste of your bread!

The wild bacteria and yeasts found in the area you live, give a unique flavor combination to your sourdough starter. So all you folks out there who are after that famous San Francisco sourdough bread, I’m afraid you’ll have to move to San Francisco.

Don’t worry, if relocating is not an option, all the other tips on this list should make your bread sour enough.

FUN FACT: Sourdough starter takes a few months to adjust flavors to its new environment, so if you really want to bake San Francisco bread at home, grab some San Fran Starter, and bake like crazy in those first couple of months before your starter has a chance to change!

Summary of Adjustments that can Manipulate the Sourness of Sourdough Bread

Here’s a table with all the main ways to adjust sourdough bread sourness. You can use all or some of these until you get the perfect sourness in your loaf.

Stage of Sourdough Bread ProcessMore SourLess Sour
Sourdough Starter StageUse whole grainsUse white flour
Use ryeDon’t use rye (white flour only)
Refresh after peakRefresh before peak
Refresh less oftenRefresh more often
Mix hooch inPour hooch out
Mix vigorouslyMix gently
Use mature starterUse young starter
Use after peakUse before peak
Use small amount of starterUse more starter
Stiff starter/low hydrationWet starter/high hydration
Use prefermentMake without preferment
Bulk Fermentation stageLong fermentShort ferment
Don’t add fatsAdd fats
Add rye flourUse white only
Cooler temperatureWarmer temperature
Use warmer waterUse cooler water
No baking sodaAdd baking soda
De-gas more oftenDon’t de-gas
2nd Proofing stageLonger time with cooler temperatureShorter time in warmer temperature

Check out my online course to learn how to master great sourdough bread using different flours, techniques and adjusting your schedule to suit your own needs.


I've been baking sourdough bread at home for years now and have had a journey full of successes and failures. This has given me great experience in understanding what makes a good bake!

Recent Posts

Sourdough bread is super tasty, but did you know that you can adjust it's flavor quite considerably just by making a few tweaks in the process? I personally LOVE the SUPER SOUR flavor of sourdough bread, but my kids prefer a more mild tasting sourdough. So I learned what makes sourdough bread sour, and adjusted accordingly to get the results I wanted! I share with you 18 tips that will change the sourness of you sourdough bread, so you can make you bread just how you like it! #sourdough #sour