How Does Sourdough Starter Work and How to Get One Started?

How does a sourdough starter work? 

The simplest way to explain it, it is your natural yeast in your sourdough bread recipe. It is what is going to make your delicious sour dough bread rise. 

When I first started making sourdough bread for my husband, I was rather frustrated. There was so many blog posts out there with different sourdough recipes for starters and breads.  But I never could seem to keep a starter alive… as for my bread?

Well, it wasn’t like those picture perfect Pinterest breads, that’s for sure. 

The taste seemed to be good, at least that’s what my husband told me, but it never got a good rise or looked real pretty. 

That’s because my starter wasn’t strong and active. Without a strong active starter you will not get a good rise with your bread, which will then hinder how pretty it is when baked.  

If you are like me and need to eat gluten free, make sure to check out my post on how to start a gluten free sourdough starter. Along with how to make a good gluten free sourdough bread. 

So, why and how does a sourdough starter work exactly?

There is a whole bunch of science behind how a sourdough starter works, but essentially you are activating the good bacteria in your flour with the environment to create a wild yeast. 

Once it is activated, these microorganism will form carbon dioxide bubbles which is what will make your bread rise. In a sourdough bread you do not need a commercial yeast, you are creating a wild yeast that will do the same work for you and is much healthier too!

Another word you may have heard a sourdough starter called is levain. So don’t be fooled if you read a recipe that says either sourdough starter or levain. They are the same thing. 

The one thing to always remember is that you want you levain or sourdough starter to be good and active to make bread. You can use the discard in many other recipes that you don’t care if they get a good rise. Some common sourdough discard recipes are cinnamon rolls, crackers, waffle/pancakes, or even pizza crust!

Is sourdough bread healthier for you?

Now let’s address the elephant in the room.

The health benefits behind sourdough. I’m sure you have read all over the internet how sourdough bread is much healthier for you. It has been become quite the craze since 2020 as everyone seemed to start looking into their health more.

The benefits of a sourdough bread, specifically gut health, are incredible. Sourdough use to be an “old time” practice but is quickly making a come back and for good reason!

The main reason I believe sourdough is making a comeback is because of the amount of people suffering from gut inflammation. It seems there are more people that can’t tolerate gluten or all purpose flour then those that can. 

Disclaimer: I am not a doctor and this is not medical advice. Any and all information is based on the authors opinions, own research, and decisions for her family. Please always consult a medical professional with questions and concerns.

The fermentation process that happens with the sourdough starter can lead to different probiotic and prebiotic properties that form within your loaf. These properties are incredibly healthy for your gut, which makes a sourdough bread easier on your gut then a regular yeasted bread. 

In addition, it is said that sourdough bread is easier to digest then yeasted bread. Let’s be clear, that sourdough bread is NOT gluten free. But with the fermentation process of the starter and bread, it breaks down some of the enzymes in the wheat which makes it easier to digest. Studies are showing that this may be helping those that are having a hard time processing gluten. 

Please note that this is referring to gluten intolerance. Not celiac. If you have celiac, I would not try a sourdough bread using all purpose flour. See the link above at the beginning of this post for my gluten free starter and bread recipe. 

Lastly, some studies are showing that sourdough bread is helping to keep blood sugars in a healthy range. It has shown that sourdough bread has a lower glycemic index and glycemic load then non-fermented breads. 

The glycemic index is how much your blood sugar rises after 2 hours of eating food and the glycemic load determines how quickly the blood glucose spikes. Having a lower rate in both of these helps to keep your blood sugar regulated and steady.

So back to the question, is sourdough bread healthier for you? In my opinion it has a lot more health benefits than a regular yeasted bread and you may see some wonderful results getting it into your diet, not to mention its unique flavor!

What flours do I need to start my sourdough starter?

Let’s talk about how you are going to get a sourdough starter started. 

The problem I was having for so long was my sourdough starter wasn’t strong enough. I was not getting a very bubbly product and the end result in my bread was kind of blah. Definitely not like all the pictures I was seeing online of bread bakers.

This left me frustrated. All the recipes out there talk about adding all purpose flour and water to start theirs. Why wasn’t mine working?

It turns out, it was the type of flour I was using for the very first time. 

You see, most recipes out there tell you to start with all purpose flour and water and to feed with that. This doesn’t work very well because the all purpose flour doesn’t have as many microorganisms that your starter needs to start fermenting. 

When I read I needed to start with a more powerful flour, that’s when I knew I was doing it wrong all along. To kick start your starter, the best flour to use is a whole wheat flour or a rye flour. That is because a whole-grain flour contains more nutrients and microorganisms than an all-purpose flour, which is what you starter needs to really get the fermentation process going. 

After the initial start, you will just use all purpose flour and water to feed it. 

Do I need special equipment?

Disclaimer: This post contains affiliate links. As an Amazon Associate I may earn a small commission on qualified purchases at no additional cost to you.

To make a strong sourdough starter, the measurements have to be just right. That was another step I was getting wrong. 

Almost in every sourdough starter recipe I found, it would say to discard half of the starter and feed equal amounts of flour and water. While this is pretty close to what I do, it is important to measure in grams the exact amounts. Once I started doing that, my starter became very active and strong.

In order to measure your ingredients, you will need to get a digital kitchen scale. I just got mine on Amazon. You can also find them at your local Walmart or Target. 

The only other equipment you will need, is a quart mason jar to get started or I like to use these weck jars.

They are larger and my sourdough starter never bubbles over when it is good and active, usually on day 5-8. I just remove the rubber ring and clips and gently place the lid on for the weck jars. You do not want an airtight container. 

You will also need a wooden spoon or spatula to stir. Stay tuned, wooden sourdough spatulas are coming on my website soon!

Filtered water vs tap water?

This is another big question that lurks the internet.

Everywhere you look, you will find a recipe that says to use filtered water for your starter. Now this is true to some degree.

I use my tap water in my sourdough starter and in my sourdough bread with no problems. However, I am on my own well and I know my water is good. 

If you are on city water, I would highly recommend using filtered water. This is because city water can be chlorinated and that will disrupt the fermentation process. 

If you are on city water, make sure to always use filtered water to ensure the health of your starter. 

The perfect way to start a sourdough starter.

Starting a sourdough starter is a process. You will need some time and patience, but luckily it is not labor intensive. Make sure you give yourself around 5-8 days before you want to bake bread in order to get a good active starter. Everyone’s kitchens and environments are different, so the timing before your starter really takes off will be different. But a good 5-8 days should do. 

Day 1:

• 60g whole wheat
• 30g warm water

Take a quart size mason jar and add your whole wheat flour and water to the jar. Mix it well with a wooden spatula or spoon. Cover with a piece of cloth, or I like to use a coffee filter. Secure it with a rubber band and let it sit on your counter for 24 hours.

Day 2:

After 24 hours, remove your cover and rubber band. If your starter has a few air bubbles in it, you are ready to move onto the next step. If it doesn’t, cover again and let it set for another 24 hours. At the end of the second 24 hour period, if you still don’t see air bubbles, throw it out and start over.

Discard all of your starter except 40g. This day you want to completely throw out your discard. You can not use it in any other recipe. Feed your starter the measurements below.

• 40g starter
• 125g warm water
• 140g all purpose flour

In the same jar that your starter is in, add in warm water and all purpose flour. Mix well, cover, and set on the counter for 24 hours.

Day 3-8:

You will continue to discard all your starter but 40g and feed it 125g warm water and 140g all purpose flour. At this point you can use the discard in other sourdough discard recipes like waffles, crackers, cinnamon rolls etc. Google “sourdough starter discard recipes” you will be amazed at what you can do with your remaining starter!

You will know your starter is ready to bake bread when it has a lot of bubbles and is at least double in size. This means you have a healthy sourdough starter. The amount of time this takes is different for everyone. 

It is going to depend on the humidity and temperature of your kitchen. The fermentation process loves warmer temperatures. So depending on how cool your home is will determine how fast your starter takes off.

If your home is exceptionally cool, try sticking your starter in an oven with the light on, by a heater vent, or next to a wood stove during the winter months for best results. 

Some people swear by doing the float test to see if it is active. This is where you put a little bit of unstirred sourdough starter and drop it into a glass of water. If it floats it is active, if it sinks it is not. I never do the float test and just watch for the bubbles and doubling in size. 

​What is the maintenance on a sourdough starter?

If you plan to bake bread every day or even a couple times a week, it is wise to keep your starter on the counter and feed it every single day by following the above instructions of 40g starter, 125g warm water, and 140g all purpose flour.

I find that the best bread comes from a well fed and active starter that never gets “put to sleep”.

Now if you are not going to bake a lot or have a busy week/month ahead you can put your starter to sleep. Basically all this means is it stops the fermentation process and it doesn’t need to be fed so regularly. It gives you a break!

You do this by sticking your jar of starter in the fridge. Some say not to leave it in there longer then 2 weeks to a month without feeding it, but I have definitely left it in my fridge for longer periods and been totally fine!

When you are ready to wake it back up, pull it out of the fridge and let it come to room temperature on the counter. Give it a stir, discard all but 40g of starter, and feed it the above measurements. 

I find that it usually takes about 2 feedings to wake it back up. So I usually only put it in the fridge when I know it will be weeks before I make bread with it.

What is the brown liquid on the top?

When your starter goes to sleep in your fridge, you may notice a grey-ish brown liquid on the top when you go to pull it out. This dark liquid is called the hooch and is totally normal. It is a sign that your starter is hungry.

The hooch appears when your starter is running out of starches and sugars that are found in the flour. It is the naturally occurring alcohol that happens in the fermentation process. 

It is harmless and nothing to be concerned about. However, when you see the hooch on your starter you know it needs to be fed. 

Simply pour off the hooch into the sink, stir your starter, discard all but 40 grams, and feed it with the above measurements. 

The color of the hooch is usually grey or brown in color. Don’t get it confused and think it is mold. 

​When to know if your starter has gone bad and should be thrown out?

​If mold appears on your starter throw it out, clean your jar real well with hot soapy water, and try again. 

If your starter has pink, yellow, orange or black spots or streaks growing on the top it likely it mold. It is best to just throw it out and start a new starter. 

Along with the color, if you see a fuzzy substance on the top, it is mold. You do not want to continue. Throw it out and start over. 

One thing to remember is with this being a wild sourdough project and creating a wild yeast, your starter is going to have a multitude of smells going on. Do not just go off of smell to determine if your starter is bad because it can take on so many smells.

When your starter needs to be fed, it will have a very powerful sour smell. When my starter is being fed every day and super active, I notice it has a slight sour smell with a hint of sweet. 

Smell will not be a good indicator to determine if your starter has gone bad. The best practices would be to rely on sight to look for signs of mold rather then on smell.

Now that you have a good active sourdough starter going, you are ready to make your favorite homemade sourdough bread! Come back next week for my simple and delicious sourdough bread recipe using this leavening agent to get your bread to rise.