Is Sourdough Bread Low Carb? 

Bread can be one of the hardest things to give up when you’re on a keto or any kind of low-carb diet, so a lot of people start looking towards sourdough bread as a low-carb alternative. But is sourdough bread really low carb? The answer is a little more complicated than yes or no, but a very simplified answer is this.

Due to the fermentation process that it goes through, sourdough bread is relatively low carb compared to other types of bread, but in general, it’s still not considered a low carb food. However, depending on the type of flour used, sourdough bread can be eaten in a keto diet.

Basically, it all comes down to the type of flour you are going to use for the starter and for the bread itself. So let’s see which is the best flour to use if you want to make a low carb, keto-friendly sourdough bread.

Best Flour Type to Use for a Low Carb Sourdough Bread

Here is a table with some of the low carb flour that you can use when making sourdough bread:

*The nutrition facts for 3.5 ounces (100 grams)

You might have noticed that most recipes will use a starter that is not made with a low carb flour starter, even if the bread itself is labeled as low carb or keto. This is because most low carb flour can’t ferment, so it can’t make a starter, and a sourdough bread made without a starter is not a sourdough bread.  It might be bread, but not sourdough bread.

But even if the starter is not made using a low carb flower, due to the fermentation process that it creates, the whole bread will have fewer calories than it would have without it. This might sound a little strange but let me explain how things work.

Why Sourdough Bread Has Fewer Carbs Than Other Types of Bread

The starter is made using only water and flour. If you combine those two and leave them alone they will start to ferment, while fermenting the small bacteria that are naturally found in the flour will wake up and start to eat the sugars and the starch that are naturally found in flour. And as we all know sugar and starch are huge sources of carbohydrates.

This whole process might sound very strange at first, after all, who wants bacteria in their food? But there is no need to worry, those are good bacteria that are known as probiotics, and they are the same bacteria that can naturally be found in our gut. If you want to know more about probiotics in sourdough, what they do there, and why you can’t make sourdough bread without the you can check out my article: Does Sourdough Contain Probiotics? (+ What They Do)

When making sourdough bread you will use some of the starter, and combine it with the rest of the ingredients and let it grow for a few hours. While growing the probiotics in the starter will start eating all the sugar and starch that they can find, which will drastically reduce the carbohydrates in the bread. And make the bread grow at the same time.

Most types of bread use commercial yeast, which does more or less the same thing, but just not as efficiently as the starter does.

Bread that uses baking powder or baking soda won’t do this and they will make what is known as soda bread, which is something completely different from sourdough bread, if you want to know why those types of bread are different you can check out my article: 9 Differences Between Sourdough Bread and Soda Bread

From what I’ve noticed a lot of low carb sourdough bread recipes tend to use baking soda or baking powder instead of a starter. This is because you can’t make a starter with low carb flour, and this will add some carbs to the bread. But using the starter will also reduce the overall carbs of the bread.

How Many Calories Does a Sourdough Bread Have?

Now let’s discuss the important part, how many carbohydrates does sourdough bread have.

*The cabs are calculated per slice

In just a moment I will tell you the exact recipe for the Low Carb Sourdough Bread that I listed in the table, as well as the macros, and why it only has 2.6 g net carbs.

But what I want to point out using this table is that due to the starter, which eats the sugar and starch, any sourdough bread will have fewer carbs than a bread that doesn’t use a starter.

Sourdough bread can be made using every type of flour out there, and while the taste and texture will differ from flour to flour, it will still taste like sour bread. So if you were to use almond flour instead of all-purpose flour you will still obtain a sourdough bread that tastes like sourdough bread. So you are not just settling for a low carb, but less tasteful alternative.

Now let’s look at the low carb sourdough bread recipe I used.

How to Make a Low Carb Sourdough Bread

Ingredients

• 1 cup water — (100-110°F)
• 1/4 cup sourdough starter — at room temperature
• 3/4 cup vital wheat gluten
• 1/4 cup oat fiber
• 1/4 cup soy flour
• 1/2 cup almond flour
• 1/4 cup flaxseed meal
• 1/4 cup wheat bran — coarse unprocessed
• 1 1/2 tablespoons olive oil
• 1/2 teaspoon salt
• 1 tablespoon Splenda – or other sweeter

Recipe

The Sourdough Starter

This will take quite a while to make, at least one week, but there is no other way around it, this is how sourdough is made. But the good part is that once you make it you can use it as many times as you want, as long as you maintain it.

1. To make the starter you will mix 100 grams of wheat flour with 100 grams of water. My advice is to use a digital scale, as it’s very important to get the quantities right. After you mix them loosely, put the lid on the jar, (don’t tighten it, the mixture needs air) and store it in a room at a moderate temperature. ( I store mine in the kitchen as it doesn’t get cold overnight)
2. The next day at around the same hour, take a spoon and remove the mixture from the jar until only 50 grams are left, and then add in another 50 grams of flour and 50 grams of water and mix well.
3. And you will repeat the last step for at least one week. And when you make the sourdough bread, instead of throwing the discard, you will use it in combination with the rest of the ingredients to make the bread. 

This is overall a very simple starter recipe, there are different ways in which you can make it, and with different types of flour (most low carb flour doesn’t work to make a starter), different feeding schedules, and different proportions. But this basic starter is what I usually used and it always worked.

A few things that you need to keep in mind is that the starter will usually smell strange, but that is ok, starters can have a wide range of smells that can change from day today. The only time you should worry about your starters is when there are no bubbles, it doesn’t rise and fall, and there is mold on it. If none of those things are happening your starter is completely fine.

If you want to know more about how a starter should act and look check out my article: Is my Sourdough Starter the Right Consistency? (Beginner Guide), and if you are worried that your starter has gone bad check out this article: Is Homemade Sourdough Bread Safe? (The Final Verdict)

Now let’s continue with the rest of the recipe.

The Sourdough Bread

1. In a bowl combine the vital wheat gluten, oat fiber, soy flour, almond meal, flaxseed meal, and wheat bran together.
2. In a separate bowl place half of your mixture and combine it with ½ cup of warm water and ¼ cup of starter, and mix everything together. Now loosely cover the mix with a lid and set it aside on the cupboard for 1 or 2 days. Store the other half of the ingredients in the fridge.
3. After 1 or 2 days add olive oil to the mixture that you left on the counter and mix everything.
4. Now take out the mix from the fridge and combine it with salt and a sweetener (in my case Splenda)
5. Now it’s time to mix everything together, if you have a dough mixer this would be a great time to use it if you don’t you have to knead the dough for about 15 minutes. 
6. After you are done mixing it’s time to form the loaf.
7. After that place the loaf in a tray, a dutch oven, or a loaf pan, cover it with a damp towel and let it rise for 2 hours in a warm place.
8. After the dough has risen it’s time to place it in a preheated oven at 350 degrees for 45 minutes to 1 hour.
9. When the time has passed remove the bread from the oven, place it on a cooling rack and let it rest for 2 hours. This is a very important step as the bread is partially raw on the inside at this point, you want to let the heat that is trapped inside the bread cook the bread completely.
10. Enjoy your low carb sourdough bread!

Macros

Net Carbs

Final Thoughts

Sourdough bread is not necessarily low carb, but as you can see from the recipe it can be.

Due to the unique way sourdough bread is made it will always have fewer carbs than bread that uses commercial yeast, but in most cases, this is not enough to make it a good option when following a low carb diet. But as you’ve seen if you are using a recipe that is made to be low carb, you can make sourdough bread that can be enjoyed while following a diet.

When it comes to low carb bread there are a lot of great commercial options out there, but in the case of low carb sourdough bread, I haven’t seen any. So If you really want low carb sourdough bread you will have to make it yourself. And while it can take a while to get everything ready, especially the starter, the rest of the process is quite easy.

If you want to make your own low carb sourdough bread I suggest you read the articles that I mentioned throughout this one, most of them are meant for beginners and explain things as simply as possible, without removing any of the important parts. So if you are ready to start baking make sure to check them out.