Care and Feeding of Sourdough Starter
I originally wrote up these notes in July 2008, and added to them over the next couple years. I've emailed these to people when I gave them some of my starter, adding to and adjusting the text each time I do. I’ve also included some links at the end to guidance from people who know more about this than I do.
Keep your starter in a glass jar with a lid. You can use an old salsa jar or a jam jar, or even a water glass covered in saran wrap. Plastic would work too, but avoid letting the starter touch metal for a long period of time. (It’s acidic, so it might pit the metal or pick up a metallic taste.)
It’s surprisingly hard to kill a starter. You can ignore it in the back of the fridge for months, but when you take it out and feed it it will come right back. If it smells funky, it’s probably just hungry. (More on feeding below.)
Starter isn’t as fast as commercial yeast. It takes time to make flavor. Use your fridge to make the bread-making fit your schedule: at any point in the process, you can put the dough in the fridge for up to a week. Just give it half an hour to an hour on the counter to warm back up, before you go on to the next step.
Get the starter ready.
- Take the jar out of the fridge. Feed it ½ cup of water and ½ cup of flour.
- Wait a couple hours for it to get bubbly.
- If it’s not bubbling after 12 hours, feed it again and wait another few hours. (It’s not dead, I promise; it’s just tired.)
- Set aside ½ cup of starter for next time. Put the rest in a nice big bowl. Remember that the dough will double in size — or triple if you let it go too long — so pick a bowl that won’t overflow. Partly dried bread dough is a pain to clean off the counter.
- Put the ½ cup of starter back in the jar, and then put the jar back in the fridge.
Mix the dough.
- Add, by weight, 14 oz of water, 20 oz of flour, and 0.2 oz of salt to the bowl. That’s about 2 cups of water, 4–5 cups of flour and 2 teaspoons of salt, if you don’t have a kitchen scale.
- Mix well, and knead as needed if it’s too stiff to stir.
- Wash the spoon or mixer paddle you used. It’s way easier to clean bread dough before it hardens. After it hardens, you’ll need to soak it.
Let the dough rise.
If you like big rustic-looking bubbles, put the dough straight into the bread pan after you mix it, and let it do one long rise before you bake it. How long? Maybe three to five hours. I’ve done overnight too, and that usually works. Otherwise, keep going with the steps below.
- Cover the bowl with saran wrap and ignore it for 1–3 hours. It should have risen enough that you can poke it with a finger and see the indent stay in. The warmer the starter is, the faster it rises.
- Punch the dough down and knead a little bit, to get rid of the big bubbles.
- Put the dough in a greased bread pan, cover with saran wrap, and wait another hour or so.
- Bake in a preheated oven at 350 °F, for about 45–60 minutes.
- It’s done when the top is golden brown, the center is at about 180 °F, and it sounds hollow when you knock on it.
- Cool for about 10 minutes, then take out of the pan.
Happy starter smells like bread and has little bubbles all up and down, and maybe a light froth on the top. Kind of like cappuccino foam.
Hungry starter sometimes smells odd — like apples or nail polish remover. That’s fine. It’s just stressed out because there’s nothing to eat. (You’d be stressed out if you hadn’t eaten all day too…) Feed it and give it some time by itself. If you keep bread dough in the fridge more than a week, it might start to get hungry and smell this way too. Usually, that smell bakes out; sometimes it doesn’t. Just bake with it anyhow, and see what happens.
If there’s a thin watery layer on top, that’s totally normal; just stir it back in. It might smell kinda boozy from the yeast making alcohol. Don’t drink it though — it doesn’t taste good.
I like to feed the starter with rye flour and stir it with a knife. The knife is easier to clean than a spoon. Rye flour doesn’t have as much gluten, so it makes the starter easier to stir, and rye grains have lots of natural yeast on them.
If there’s mold growing on your starter, you can probably still save it. Scoop off a good inch below the mold, and throw that out. Get a new clean jar, and transfer about 2 tablespoons of the starter from the bottom of the old jar. Feed it and wait 12 hours, then feed it again. Put it in the fridge long enough to convince yourself there’s no mold growing in the new jar.
A little more about how sourdough starter works
Starter has two ingredients, flour and water, and it has two things growing in it, yeast and lacto-bacteria. The yeast eats starch from the flour and makes carbon dioxide (bubbles!) and alcohol. The bubbles make bread rise, and the alcohol evaporates in the oven and makes it smell good. The lacto-bacteria is the same great stuff that makes yogurt and sauerkraut, and it’s what makes things sour and tasty. Both yeast and lacto-bacteria go dormant when they’re cold — that means as long as you refrigerate the starter, you don’t have to feed it. (It also means if you keep the starter at room temperature, you do need to feed it. Typically once or twice a day.)
You can play with the balance between yeast and lacto-bacteria in your starter by adjusting how much water you give it and how often you feed it. A thick, frequently-fed starter will have more yeast; a thin seldom-fed one has more lacto-bacteria. There are forums online where people have written up their feeding schedules of so much flour/water and so many hours. I don’t. You can be as precise or as loose as you want.
The recipe above is just a weight ratio — 10 parts flour, 7 parts water, 0.1 part salt. You can scale it way up or way down. One cup of water weighs 8 oz, one cup of flour weighs 4–6 oz, one teaspoon of salt weighs 0.1 oz. At a 10:7 ratio, the dough is also soft enough you can make flatbread by scooping a peach-sized blob of dough and spreading it out in a hot greased skillet. If you find the dough too sticky for loaf bread, try a 10:6 ratio instead.
If you have the fridge space, you can mix up a bunch of dough when you have time, and then keep it in a big tupperware or covered bowl until you want to make bread. If the tupperware is big enough, you can even mix in it. I like the flavor best after letting the dough hang out in the fridge for almost a week.
If it’s not too hot out (60–70 °F) you can mix the dough up and put it in a greased pan to do one long slow overnight rise. Then, in the morning, either bake it or put it in the fridge. If it’s hot, this might not work. If it’s 50 or 60 °F in your kitchen at night, either give it longer to rise, or let it hang out in a different part of the house.
Sourdough pancakes are a tasty and easy way to keep your starter “moving”. In a big measuring cup with a spout, beat an egg with a generous splash of milk. Add some starter and small spoonful of baking powder. Stir in enough flour to make the right batter consistency. (Or if you have a pancake recipe you like — maybe one that has actual measurements — just add half a cup of starter to it.)
Alex French Guy Cooking: A Non-Baker’s Guide To Making Sourdough Bread — a brief video that may also be helpful since you can actually see how things look.
The Perfect Loaf: Sourdough Starter Maintainence Routine — a more detailed discussion if you’re after specific results.