What the heck is this starter that everyone talks about? | Sourdough Cheat Sheet

Left: Day 1, Right: Day 2

Sourdough cliff notes

If you’re here, you probably have a little idea of what starter is, or maybe you don’t like me when I began the sourdough journey. All I knew was that this step would take longer than I’d like to make my bread.

I was fuzzy about the whole starter thing before I began. But let me explain super briefly and take away the mystery and fear of this thing- starter.

First off, abandon your efficient-1,2,3 recipe persona for a second. This is not just another recipe. It’s a way.

Enter kitchen zen. By way of sourdough. It will take time, patience and eh, a little sensory exploration. Don’t worry, you start with doubt but end up loving the thing like it’s your baby or a tomodachi pet.

What you need to make starter..

  • All purpose flour
  • Whole wheat flour, if you have it
  • Water
  • Scale
  • Small container
  • Rubber band
  • Paper towel

What is starter?

Starter is living yeast. The small packets of active live yeast is a compressed form of this live yeast. Instant yeast is reliable but not as tasty and not as healthy as bread made with fresh, wild yeast. So, what you are doing when you make starter is making your own yeast so you never have to buy the packets stuff again.

Literally, starter is a mix of equal parts flour and water. I start with about 50 grams flour and 50 grams water. You mix them in the container and it gets the wild yeasts active. Once it starts to bubble it means it’s active and may be ready to use to make your dough rise, instead of yeast. This can take 5-10 days if you’re starting from scratch.

If you’re lucky, someone can help you get a head start and share some of their mature starter with you. You can mix that into yours and it will instantly make yours more mature. Its a pretty cool thing.

This is the process of sourdough making. It all starts with Starter: 

  • Make starter (or get it from someone) =>
  • Starter matures in around 5 days =>
  • Feed starter (more flour and water) =>
  • More bubbles are produced =>
  • Is it ready? =>
  • See if it passes the Float Test (this means its ready to use) =>
  • Passes Float Test =>
  • FINALLY Make the bread recipe with your starter

What to I do after I mix it. It seems too easy?

It is easy. Now, you have to wait 2-3 days. You have to let nature do the work on this one. Natural yeast in the air and flour will activate and create bubbles. That’s what you want. And it takes a little time.

Keep it ideally in an environment where its 70-80 F. This makes it go a little faster. It should start to bubble a bit after a day or so. When it smells a little like stinky cheese, it’s ready for its first feeding. “Feeding” just means discarding half and adding more flour and water. This really makes it feel like it’s a pet.

When do I know it’s ready?

It should be bubbly and smell sweet and kind of like apricot. It will have risen a lot from its original spot. But, the best way to be sure is to do a Float Test.

Float test: Get a cup of room temp water. Put a spoonful of starter in it. If it floats, its ready- Yay! It has enough Carbon Dioxide in it. You can begin your bread recipe.

IF it doesn’t, its either too ripe (sour smell) or needs more time to mature. You can wait longer.

Whatever you do- DON’T START OVER (you’ve already started activating some of the yeast believe it or not, don’t throw out your hard work). It’s practically impossible to kill your starter. Worst case, discard half and replenish with more water and flour, always equal parts. Quantity doesn’t matter as much, just keep it equal parts flour to water. Wait some more.

Once you pass the float test… go here: How to Make your First Sourdough Loaf

How do I store it?

In the first 1-5 days, leave it out at room temperature. Once its bubbly and more mature after 5 days or so, you can move it to the refrigerator. Keep it covered with a paper towel and rubber band. Then, discard half and feed it with more flour and water, ONCE a WEEK.

What happens if I kill it?

It’s almost impossible to kill. Even if you forget about it in the refrigerator and a black crust forms at the top (its happened to me), it is not dead or bad. Scrape off the crust (its just discolored flour) and discard half and feed it some more flour and water, always 1 to 1.


Starter Recipe


  • 50g flour (all-purpose or bread if good)
  • 50g water (filtered best)


  • ½ cup flour 
  • ½ cup water


Mix together flour and water in a small container, like mason jar or plastic cup. Cover with a paper towel and put a rubber band around it. It needs to breathe so don’t seal it with a hard lid. Leave it at room temperature for 2-3 days. Notice the smell now, then check in a day or so.

At day 3, it should start to smell a little like stinky cheese or sour. If it doesn’t, wait another day.

When it smells stinky, remove 80% of it and through it away. Add another 50g or ½ cup flour and 50g or ½ cup water. Mix well. Cover the same way and let it sit out at room temperature. Repeat this process the same time each day.

Do it for at least 2-3 days more and then we can see if its ready for the next step: The Float Test.

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Feeding your sourdough starter. How should it look like? Here is mature vs. young from the fridge. I keep mine in the fridge after 1 week of feeding it equal parts flour and water. After feeding, wait until it gets bubbly (5hrs to a day or so) and then do the float test to see if it’s ready to make bread! . Young starter: about 10 days old Mature starter: over a year . . The mature starter has a beautiful smell of flowers, or nectarines in the summer. The young one is much different and smells somewhat like Bleu cheese. But it just needs more time to flower into its floral sweet smell. Stick with it!! With age it gets better. 👵🏻. #sourdoughbread #starter #sourdoughstarter #homemadebread #howtomakebread #naturalyeast #naturalyeastbread #veganbread #vegan #homebaking #levain #wildyeast #artisanbread #countryloaf #countrybread #sauerteigbrot #naturallyleavened #realbreaf #breadbosses #lievitomadre

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Sourdough can test your patience, but it’s so worth it. Congratulations on taking on this beautiful challenge!

For your sourdough 911 needs, find and follow me on instagram: @chefjoannas

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