What Is Sourdough Discard (Everything You Need to Know!)

Sourdough discard is an essential part of sourdough baking, so what is sourdough discard? I'll explain everything you need to know about it, how to use it, and how to keep it in your refrigerator so you can bake your favorite recipes any time of day!

I first received a sourdough starter from a friend in the Summer of 2019. I had no idea what I was doing! Then the pandemic hit and just like everyone else, I was knee deep in sourdough recipes and sourdough bread. Since then, I've perfected my recipes and bake with my sourdough starter or my sourdough discard at least once a week, if not more!

At first, I threw away my sourdough discard every time I fed my starter, not realizing the magic that sourdough discard is! Now, there is always a jar of sourdough discard in my refrigerator to make sourdough bread with discard or New York style sourdough bagels with discard.

So What is Sourdough Discard?

Sourdough discard is the portion of your sourdough starter that is removed or "discarded" during the feeding of your sourdough starter. A sourdough starter needs to be regularly fed with equal parts flour and water to keep it active and healthy and ready to bake bread with.

During the feeding process, a portion of the existing starter is discarded before adding fresh flour and water. This discarded portion is called "sourdough discard".

Don't be fooled though, just because it's called discard doesn't mean it's useless! In fact, I love baking with my sourdough discard! Not only are you minimizing waste by using the sourdough discard, it adds a delicious tang to recipes like chocolate chip cookies and skillet cornmeal.

Sourdough Starter vs Sourdough Discard

So what exactly is the difference between an active sourdough starter and sourdough discard? Let me explain.

Your sourdough starter is like the heart and soul, the hero, of your sourdough bread adventure. It's a bubbly mix of flour and water full of wild yeast and friendly bacteria. This lively mix is what makes your bread rise and gives it that amazing tangy, sourdough flavor. You have to feed and maintain your sourdough starter in order to make bread on a regular basis. No bubbles, no bread!

There's nothing player in the sourdough game, and that is the sourdough discard. When you feed your starter, you have to take out a bit of it before adding fresh flour and water. That bit you take out? That's your sourdough discard. Keep it in a mason jar in the refrigerator. You can use it in all sorts of recipes like pancakes, waffles, or even more pizza dough. It's like giving your starter's castoffs a second chance to shine.

How Do You Feed A Sourdough Starter?

Feeding a sourdough starter is essential in your sourdough journey. First, grab your kitchen scale. Yes, you need a kitchen scale! It's the most accurate way to bake bread. All you have to do is add 100 grams of starter, to 100 grams of water and 100 grams of flour. Mix well and let it sit on the counter until it doubles in size. This should take 8-12 hours. Once it gets nice and bubbly you can bake with it.

How Do I Activate Sourdough Discard?

It's simple! Grab a clean jar and add 100 grams of sourdough discard, 100 grams of fresh flour, and 100 grams of water to the jar. Mix well and cover it loosely. Let it sit for 8-12 hours or until it doubles in size.

Since it is sourdough discard, it might be a little slow to rise. Don't panic! If that happens, simple feed it again. Repeat the process of feeding it until it becomes bubbly and active. Then make some same day sourdough bread!

Why Do I Have to Discard When I Feed My Starter?

Here's a graphic to explain the life cycle of your sourdough starter.

Now that you have seen the life cycle, let me explain why we are discarding a portion of your starter every time you feed it. Discarding a some of your sourdough starter helps maintain its health and acid balance. Here's why you should discard some of your starter each time you feed it:

• It helps control growth: Sourdough starters are essentially colonies of wild yeast and bacteria. Feeding them with fresh flour and water provides nutrients for these microorganisms to grow and multiply. If you allow the starter to constantly grow without discarding any of it, it would grow and grow, requiring more and more flour and water to feed it. You'll never be able to use that much sourdough unless you are baking for a bakery or a business. By discarding a portion before feeding, you control the growth and maintain a small and manageable quantity of starter.
• Keeps consistency in your sourdough starter: Regularly discarding and feeding your starter helps maintain its consistency. If you don't discard, the proportions of yeast and bacteria to flour and water can become imbalanced, leading to inconsistent fermentation and potentially affecting the flavor and texture of your sourdough bread.
• Keeps the sourdough flavor in check: As the sourdough starter ferments, it produces acids, primarily lactic and acetic acids, which gives the starter its classic sour flavor. By discarding a portion of the starter, you remove some of the acidic byproducts. This makes sure that your sourdough doesn't get too acidic, hence making it too sour and effect the yeast doing it's job while the bread bakes.
• Keeps your sourdough starter healthy: Regularly discarding and feeding your starter helps keep it healthy. It removes any potential contaminants or unwanted bacteria that may have grown or gotten into your starter. It also ensures that the yeast and bacteria in the starter remain active and robust.

Storage Tips

Sourdough discard should be kept in the refrigerator in a mason jar or an airtight container. As the discard sits in the refrigerator the texture will change. It will become more liquid and less thick. It's best to keep the starter in the refrigerator for about 2-3 weeks. To be honest though, I've kept it in the refrigerator longer.

You can even freeze some extra sourdough starter. Pour it into smaller, freezer safe container and freeze it for up to 3 months. Defrost it in the refrigerator and then use it in some of your favorite recipes, like sourdough discard cinnamon rolls.

What Is The Black Liquid On My Sourdough Discard?

The black liquid that sometimes forms on top of sourdough discard in the refrigerator is called to as "hooch." Check out my sourdough glossary for more sourdough terms. This liquid is a byproduct of fermentation and it is basically just made of alcohol and water. It's not something to be concerned with. Here's what's happening:

• Here's the science! Sourdough discard contains wild yeast and bacteria that are actively fermenting the flour and water mixture. During fermentation, the yeast consume sugars in the flour and produce carbon dioxide gas, which causes the mixture to bubble and rise. Additionally, the yeast also produce alcohol as a byproduct of fermentation.
• Separation: Over time, the alcohol produced by the yeast can separate from the sourdough mixture and pool on the surface. This alcohol-rich liquid is what we refer to as hooch.
• It's actually a good thing! The formation of hooch is a sign that the discard is still alive and active. It indicates that fermentation is occurring while it hangs out in the refrigerator. While hooch may look unappetizing, it's perfectly normal and safe.
• So what do you do now? When you notice hooch forming on your sourdough discard, you have a couple of options. You can simply stir it back into the discard before using it in your recipes. Another, more common option is to pour off the hooch before stirring the discard. People prefer this because some people find that its flavor too strong.

How To Add Sourdough Discard to Any Recipe

Since the discard is not being used to make any recipe rise, you can really add it to any recipe. Keep in mind you may need to adjust the water and flour ratio in the recipe, but for the most part you can add ½ cup to ¾ cup of sourdough discard to any recipe you would like.

When I make my pizza dough with sourdough discard, I add the yeast and the sourdough discard at the same time and then let it rise. When I add it to things like sourdough scones, I add all the ingredients together at the same time, mix, and then cook.

Recipes Using Sourdough Discard

• Sourdough Granola
• Chocolate Cake with Sourdough Discard
• Carrot Cake with Sourdough Discard
• Sourdough Discard Zucchini Muffins
• Brownies with Sourdough Discard
• Sourdough Pancakes

What Else Can I Do With It?

There are so many recipes you can make! I love baking with it, but you can also making the best crispy onion rings with your discard too!

Believe it or not you can use it to thicken your soups too! Its essentially just water and flour which is perfect to thicken your favorite soups with, like New England clam chowder!

Another great option is to add a little to your plant's water. I know, crazy right! There are so many good microorganisms in that starter, the plants need it too! Add a tablespoon or so per gallon of water and make sure it is dissolved well. Then water your plants with it.

Can I Start A New Sourdough Starter with Sourdough Discard?

Yes! Simply feed the discard equal parts starter, water, and flour. Mix it well and let it sit on the counter for 8-10 hours until it is active and bubbly. If it is not bubbly after the first feeding, feed it again. By the second feed it should will be good enough to bake with.