How to Make and Maintain a Sourdough Starter (aka Levain)
I'm not entirely sure how it happened, but somewhere along the way I discovered and fixated on baking bread. Specifically, I'm referring to bread made in its purest form using only flour, water, and salt. I never cease to be in awe of how three humble ingredients can transform into one of the most delicious and comforting foods. In the interest of being overly dramatic, the fact that I made these with my own two hands is pretty magical.
"Slow bread" requires a sourdough starter (or levain) so that was my first project. Levain is a mixture of water and flour that has been converted into a leavening agent through the process of fermentation. Not only is microbiology+food fun, but you need to "feed" the levain regularly and it's apparently bad luck if you don't name it. So basically your sourdough starter is a food pet. (My starters are named "Moomin II" and "Moomin III" respectively...may "Moomin I" rest in peace.)
When I first began caring for my sourdough starter, I was neurotic about feeding times and measurements. What a sweet and naive child I was in the days of yore (3 months ago). Creating and maintaining a sourdough starter is relatively straightforward. Once you get a feel for how your levain behaves, you'll develop a personalized approach.
This post streamlines what I've learned so you can create a fermented food pet to call your own. I'm happy to answer any questions about the process so just leave a comment.
I could travel down the rabbit hole on some of these topics, but in the interest of publishing this post before 2015 I'm going to try and get to the point.
What is a sourdough starter or levain?
Wild yeast are fungi and exist everywhere - in flour, on our bodies, and in the air. By fermenting water and flour, you're growing colonies of both wild yeast and "good bacteria" or lactobacilli. Here's the brief explainer:
- Bacteria or Lactobacilli - The bacteria's main job is to turn your levain into an acidic environment. This acidity contributes to the sour flavor of your bread and, more importantly, prevents "bad bacteria" from taking hold. The most common question I've seen online is, "Why doesn't the starter make me sick after weeks on the counter?" The answer is bacteria. Counterintuitive but that's why science is awesome.
- Wild Yeast - Commercial yeast can't hang in the above mentioned acidic environment so that's where wild yeast comes in. Not only does wild yeast thrive with the "good bacteria", but colonies of yeast give off carbon dioxide which contributes to the structure and rise of your bread. For the record, bacteria also gives off carbon dioxide but that isn't its main function in the levain.
In summary, your sourdough starter is a goopey utopia where wild yeast and bacteria live harmoniously. It all translates into fantastic flavor and rise for your homemade bread. If you want to geek out, take a few minutes and read this article that discusses the science in more detail.
Embrace measuring in "grams" since it's the most accurate way to approach sourdough starter maintenance and bread baking. And if you don't own a scale it's time to get on that. I have used the OXO model for several years and really like it.
A "100% hydration sourdough starter" means the levain is 1 part water and 1 part flour. In other words, for every gram of flour there's a corresponding gram of water, hence 100% of the flour is hydrated. This is the easiest starter to maintain since most recipes are written with a 1:1 ratio in mind. That being said, increasing or decreasing the hydration of your levain can alter the pH which ultimately changes the flavor profile or sourness. I haven't gone down that path but if you want to experiment there's some more info on the subject here.
Feeding and Stirring
A sourdough starter is full of living organisms (bacteria and wild yeast) that feed off of the fresh flour and sugars in the mixture. Those organisms need to be fed regularly or they will run out of food and die. Sad. Also, yeast doesn't ambitiously travel around the bowl looking for food - it's kind of lazy. Stirring the flour mixture from time to time helps expose the organisms to fresh eats. I cover the specifics of feeding under "Instructions".
Don't get discouraged by the maintenance and feeding schedule. Once your starter is mature (usually 7-14 days) you can adjust the feedings to fit your life and/or baking habits, or just throw the starter in the fridge and feed it every week or so.
I don't recommend storing a sourdough starter in a hot location, especially in the beginning when you're trying to establish the colonies. High temperatures can encourage "bad bacteria" to grow which overrun the good bacteria, hence ruining the starter. My original levain, "Moomin I", met a quick end because I thought the hottest corner of the kitchen was a brilliant location and would help it grow faster. Not so much. And my friends, you will know if the sourdough starter has gone south. No amount of plastic bags could contain the stench of "Moomin I" when I took it out to the trash. A range of 70-75 degrees seems to be a good temperature.
Once the levain is mature - bubbling, doubling, and falling predictably - then you're free to put it in the fridge with a loose cover (already mentioned above). The cold temperature "retards" or slows the fermentation which helps spread out the feedings.
Covering Your Sourdough Starter
Wild yeast needs oxygen to thrive so I don't recommend covering your starter with plastic wrap as is suggested in many posts. My preference is to simply lay a dish towel over the bowl - sometimes it's just paper towels. This prevents anything from falling in while allowing for plenty of circulation. When storing in the refrigerator, I loosely cover the container with plastic so that the gases are able to escape.
After feeding my levain, I can accurately estimate when it's going to be ready for baking give or take 30 minutes. I'm not a special snowflake, this is just how a mature or established sourdough starter behaves. It rises and falls in a consistent pattern which makes planning your baking schedule a snap. When you feed your starter and begin to see predictable behavior, you're on the right track.
For the first 1-7 days a sourdough starter will go through some weird odor stages as the various bacteria get settled. This is totally normal as long as the smell isn't foul. Like I mentioned above, you'll know when things have gone bad. Once the levain is established, the scent will transition from a sweet smell after feeding to a slightly more sour smell as the starter ripens and peaks.
Is it ready?
Gently drop a spoonful of starter into a cup of water. If the glob floats, then that means it's hopped up on carbon dioxide and ready for baking. No fancy advice here, just make sure it floats.
Multiple Sourdough Starters
I maintain two 100% hydration levains. Moomin III is 50% wheat plus 50% all-purpose flour and goes into my country loaf. Moomin II is 100% all-purpose flour and is used for pancakes and various other baked goods. I plan to try some different combinations in the coming weeks since every levain has a unique flavor profile.
I've seen pineapple juice and various other ingredients suggested as growth aids, but in my humble opinion you only need filtered water and flour to create a starter. I think the issues people run into include the following:
- Water Impurities - The wild yeast can be sensitive to impurities and chlorine (especially when trying to get established) so it's best to use filtered water for the levain. This seems to be a consistent piece of advice out on the Interwebs. I use the same water that we drink from our PUR filter/jug.
- Feeding - Feeding the sourdough starter once a day is fine for the first 7-14 days when you're trying to establish the colonies of good bacteria and wild yeast. That being said, if you feed the starter too much, the bacteria and wild yeast won't have enough time to multiply and set up shop. If you feed it too little, your micro friends will run out of food. Once the levain is established the starter is heartier and there's more flexibility.
- Flour type - Wheat flours can be finicky so if you're having trouble I recommend using only all-purpose to get a feel for the process.
- Environmental Conditions - If it's very cold in your house, the levain may take longer to get going and it can feel like things aren't progressing. Stick with it and perhaps even skip a feeding day here and there. The colder it is the more lethargic the organisms will be. If it's too hot, your starter may be overrun by "bad bacteria" (mentioned above). If that happens and the mixture smells foul, toss it and begin again.
- Patience - New sourdough starters are a tease. They often bubble up a few days into the process, but then they start smelling a little funny and the bubble activity becomes inconsistent to nonexistent. That's ok. If you go a couple of weeks and the starter isn't rising and falling on schedule then you may have an issue with one of the above factors.
- 400g filtered water
- 400g all-purpose flour (or flour of choice)
Instructions - A Starter is Born (usually matures after 7-14 days give or take)
- Day 1 - Thoroughly mix 400g filtered cool or room temperature water with 400g flour in a bowl at least twice the size of the mixture. Loosely cover with a dishtowel or similar and set in a warm (but not hot) spot.
- Day 2 - This will be your first feeding. Try to feed the starter at roughly the same time each day.
- Place the bowl on the scale, zero out the scale, and then remove and discard 400g of starter (half of the original 800g).
- Add 200g of filtered cool or room temperature water and 200g of flour to the bowl, stir, and loosely cover.
- Stir the starter from time to time if your schedule allows as this helps expose the wild yeast and bacteria to fresh food.
NOTE: Since the starter is a living thing, on Day 2 the mass will actually weigh less than 800g so technically you're taking out more than 50% when you remove 400g. This is fine and actually desirable. As you proceed down the feeding schedule, just be careful not to take out so much starter that you're left with a lot less than half.
- Day 3 - Repeat above.
- Day 4 - Repeat above
- Day 5 - Repeat above.
- Day 6 - Repeat above.
NOTE: At this point you should notice that the levain has cycled through a variety of odors but is starting to stabilize and has a familiar smell. There should also be some bubbling activity depending on the ambient temperature/environment. The goal is for the starter to bubble, double, and then fall predictably. It's not unusual or an issue if your starter isn't ready by day 7 so just keep with it. If after 2 weeks the starter still isn't rising, there may be other factors at play (see "Tricks" above).
Instructions - Maintaining and Baking with an Established Starter
Refrigeration vs Room Temperature
I bake a couple of times a week so my levain lives on the counter. My routine is to feed the starter once a day between loaves and then I shorten the feeding window to 12 hours right before baking (a more detailed timeline is below). If you only bake once every couple of weeks, you might want to consider storing your mature starter in the refrigerator. Simply take the levain out a couple of days ahead of time and resume the feeding schedule to "wake it up".
Using a Starter
I've made bread dough with levain that was 12 hours past feeding time, but my favorite loaves from a flavor perspective were made with levain used closer to when my starter reaches the "floating stage" - usually about 8-9 hours after feeding. Something to note is that I cold ferment** my dough which means the bacteria and wild yeast get to hang out for twice as long. Cold fermentation ultimately develops more flavor and acidity so that's why I don't like to a "younger" levain.
** Cold fermentation is a process by which the bread dough is put into cold storage once the bulk fermentation is complete. This means that the final proofing is extended from 4 hours to 12, giving the flavor more time to develop.
Baking and Feeding Timeline
I've adapted Chad Robertson's country loaf recipe from Tartine Bread and the bullets below explain my typical feeding/baking schedule. I'm not including a detailed recipe since this is just meant to give a general sense of timing.
- Monday through Friday - 11pm feeding
- Saturday - Bread Baking Day 1
- 11am feeding - This is where the window has been shortened in order to give the starter a boost.
- 4 to 5pm - Make the bread dough and bulk ferment.
- 11pm to12am - Shape the loaf and refrigerate.
- Sunday - Bread Baking - Day 2
- 12pm (give or take) - Once the oven has reached temperature, remove the bread from the refrigerator and let it sit out for about 20-30 minutes. Bake the bread.
- Feed the remaining starter during the day if possible, or just go back to the 11pm feeding. This is longer than 24 hours between feedings but that's ok.