Making sourdough bread at home involves maintaining a sourdough starter. This process means regularly discarding a portion of your starter before feeding it. But why? Who wants to throw away a perfectly good active starter? This complete guide explains all the details on why you have to discard some of your starter before feeding it to help you maintain a healthy sourdough starter. Also, keep reading to get all the answers to your questions related to sourdough discard, such as what to do with sourdough discard, how to store it, when to use it and more.
You might think that discarding a portion of the sourdough starter during the feeding process is counterintuitive. Before I took the time to understand the idea behind it, I experimented and even tried making a starter without discarding any of it. Well, that didn't go very well.
Not discarding any of your starter while feeding will give you a dull and weak starter that's not strong enough to make bread. You must remove about half of the starter mixture before feeding it to maintain a healthy and active sourdough starter!
What is sourdough discard?
The portion of the starter that you remove before feeding the starter that's left in the jar is called the sourdough discard. Discard is the unfed sourdough starter you put aside or in other words, sourdough discard is a byproduct of maintaining your main sourdough starter.
This might sound like wasting a lot of food, but keep reading to learn all the amazing things you can do with sourdough discard and how to minimize the amount of waste.
Why do you have to discard some of the starter before feeding it?
Before feeding the starter, you have to discard usually half of it to avoid having too much wild yeast (and acid-lactic bacteria) compete for the food you give it.
When you feed the starter, the yeast and bacteria divide and multiply by feeding on the mixture of flour and water. The natural yeasts will populate and "spread out" all over the mixture, while they feed on the sugar from the flour.
Then, since the food will eventually run out, some of the yeast and bacteria will slow down their growth and might die...your starter might end up with a thin layer of a dark liquid called "nooch". That means it is hungry, so you refresh the jar of starter with more flour and water, meaning more yeast growing.
If you keep going with the same feedings without removing any of the starter first, then that means that you won't give enough food in comparison of a growing population of yeast within your jar. This results in an unhappy or inactive starter packed with underfed yeast competing for the fresh flour. The flavor would not be as good and the yeast not be as active.
So here is a simple solution: remove half of the mixture before each feeding. That way, you will have less yeast to feed, which ensures that there is going to be enough food for the amount of yeast in the jar, keeping them strong and happy! Plus, you will control the amount of starter you have to manage.
In summary, it is important to discard for:
- Saving money (less flour used)
- Portion control
- Reducing the acidity level of the starter (lowers the amount of acid lactic bacteria), which affects flavor and gluten development
Can I not discard any of the starter and increase the amount of food I give it instead?
Usually, you feed the same weight of flour and water that's equivalent to the weight of your starter (1:1:1, 100% hydration). So, let's say you have 50g. of starter in your jar, then you feed it 50g. of water + 50g. of flour. The next day, you have 150g. of starter to feed, so you stir in 150g. of flour + 150g. of water to respect the 1:1:1 rule. You then end up with 450g. in your jar, which you will have to feed the next day with lots more flour and water. And it keeps growing, pretty fast!
If you would simply feed a larger amount of water/flour to compensate for the growing yeast population, then:
- you would end up with an excessive amount of sourdough starter that keeps getting larger
- it would be quite expensive to keep up the amount of flour you need to use
Remember, for each loaf of bread, all you need is a fairly small amount of yeast/starter to feed a few hours before mixing the dough (levain). So unless you bake many loaves each day, such as in a bakery, all you need is a small volume of sourdough starter to maintain at home.
Is sourdough starter and sourdough discard the same thing?
They are pretty much the same thing since they are both made of flour + water.
But, sourdough starter also contains a population of microbiome that's growing and thriving. Sourdough starter refers to a more "lively" mixture that is fed to use to make sourdough bread. You can also call it the "mother culture" or "mother starter".
Sourdough discard is what you remove before feeding the mother culture. It is usually a more dormant or less active mixture since it has been set aside without being fed (and also usually kept at a colder temperature which slows down the fermentation process). Sourdough discard is not as bubbly compared to your main sourdough starter.
How much do I need to discard when feeding my starter?
In general you will have to remove half of the starter before feeding it. You can weigh the starter mixture (you will need to know the weight of your empty jar to do that...) and remove exactly half of the weight of the starter mixture. Then usually you feed with an equal amount of flour and water.
In some other recipes, you might need to build up a different ratio of culture + water + flour (as for example, if making a stiff or liquid starter), but that would be mentioned.
When can I use the sourdough discard?
As explained in this sourdough starter guide, 7 days is the minimal time you will need to make your own starter from scratch, although in most cases, it will take longer, around 14-21 days. Sourdough starters keep maturing for a while even after it looks ready making your bread better over time.
I do not recommend using the sourdough discard from the 7 first days of creating your starter. During these first few days, the bacteria are competing for the space available: the "good" acid lactic bacteria (the one that gives the delicious sourness to your bread) will slowly push away the "bad" bacteria. Before that 7-day mark, your sourdough discard could contain undesirable bacteria that you don't want to use.
After 7 days, you can start accumulating the discard from feeding your starter to make recipes!
How is sourdough starter discard not that wasteful?
When you are building up your starter from scratch, you will have to discard some of it at every feeding. And during the first 7 days, you have to throw it away in the bin before you can use the discard in recipes.
But, once you have a strong established mother starter, then you will be able to keep it in the fridge to slow down the fermentation process and feed it less often. Meaning less discarding.
Also, when you make bread and use some of your starter, then you can simply feed what's left without having any discard to deal with. Bakers that make a lot of bread, such as every day, never end up with extra discard! They use some of the active starter to make their loaf on a given day, then feed what's left. The next day, the fed starter is happy and active, the baker takes some more to make another loaf, and feeds what's left. No discard left since everything is used right away!
But, if you have a fair amount of sourdough discard that's accumulating, then there are plenty of sourdough discard recipes that you can make!
How can I minimize the amount of discard I accumulate?
There are ways to have less waste while maintaining your sourdough starter.
Every time you make a loaf of sourdough bread, the portion of your sourdough starter that you use to make the bread dough is sort of like discarding some of your active starter. The only difference is that instead of discarding it, you make bread with it because it is fresh and active. Then you can feed what's left in the jar. So, if you bake often, you should not have that much excess sourdough starter to "discard".
Also, as mentioned above, you don't need that much starter to maintain since you don't need much of it for each loaf. Just maintain a smaller amount, then you won't have to feed it much flour, meaning less discard.
What can I do with sourdough discard?
Even though we call it discard, you don't have to actually throw away the excess starter (unless you are still in the 7 first days of building up your starter, see above), which feels a lot more sustainable. You can put the discard to good use and use it creatively!
Sourdough discard adds such a wonderful flavor and character to many recipes, plus it makes baked goods more tender due to the natural acidity. You can use your leftover sourdough discard to make pancakes, quick breads, banana bread, granola, cinnamon rolls, muffins and much more. One of our favorite recipes using discard is brownies! You can use it for both sweet and savory recipes.
As a side note, adding sourdough discard in recipes is not meant to be used as a leavening agent (the discard is not that active, remember?). Because of this, sourdough discard recipes also often have dry commercial yeast (or instant yeast), baking powder or baking soda included in the ingredient list to help the dough rise.
Can I use my sourdough discard to start a new starter?
Usually yes, sourdough discard is a latent and unfed starter that can be woken up. You can definitely take a small amount of your sourdough discard, bring it to room temperature and get it back on the feeding schedule! It might take a few feedings to get it active and bubbly, but it should work.
How to store sourdough discard?
If not making bread but still need to feed your starter, then simply pour the discarded part into an airtight container (such as a glass jar with a seal). You can use the discard right away or place it in the fridge for later use. You can pour more discard over a previous portion if you bake a few times a week.
Keep it sealed so it does not dry out and I recommend writing the date on the jar to know how old it is.
Can I freeze sourdough discard?
If you end up with a lot of discard and cannot use it right away within a week, then you can also freeze it for longer storage. In that case, I recommend freezing it in individual portions so you can just thaw what you need for a recipe. Simply let it defrost overnight in the fridge before using.
How long can I store sourdough discard?
I have always used my sourdough discard within a week, but I read that some bakers will keep it for up to 2 weeks.
If you leave the discard at room temperature, then try to use it within 2 days.
As a side note, the flavor of your discard will become increasingly more sour with time.
And don't forget that sourdough starter/discard is a lively mixture that is in constant change, so always evaluate your mixture by looking at it and smelling it carefully before using it: is there any mold or discoloration? Does it smell pleasant? Follow your gut!
Lisa hoult says
So I’m first time trying to make sourdough starters one is whole wheat and one is all purpose flour I’m on day #3 and the whole wheat was bubbling outta the jar this am but the all purpose not so active . I fed both of them the past 3 days since Saturday and I’m confused if I should discard and what do I do with the discard and does it go into the frig
jessica says
Hi Lisa! Thanks for your question! I would definitely discard some of the starter right before you feed it while building it. Until the starter is active and bubbly, then I recommend to throw away the discarded part each time. Once the starter reaches maturity and you use it for making bread, then you can use the sourdough discard portion for making other recipes, like cookies and muffins. Day #3 is still early when making a starter from scratch, so at this point, I think your all-purpose one just need more time and regular feeding before being active. I hope this is helpful and let me know if you have more questions! 😊
Lisa says
Thank u I woke up this am for work at 7:40 checked my starters they were quiet not like yesterday all bubbles over I didn’t feed them this am when I come home tonight I will is that ok
jessica says
Yes, for the first few days when building up your starter, you can feed it about once every 24 hours. 😊
Anonymous says
Great guide Jessica, thanks so much for sharing!
jessica says
I'm happy it was helpful!