Wild Yeast Sourdough Starter (2024)

Take your homemade bread to the next level and make a wild yeast sourdough starter at home with all-purpose flour and naturally-occurring yeast, using a clever secret ingredient.

Winter is a great time for indoor projects. This year, I wanted to tackle a sourdough starter. I had one years ago from King Arthur Flour that disappeared at some point (either after a move, or more likely a casualty of a manic, take-no-prisoners refrigerator clean-out) and have been meaning to reboot my bread making mojo.

But, “tackle” is too strong a word. Even though bread baking itself is already quite easy (yup, even yeasted bread), making a homemade sourdough starter is even easier. Why? Because you don’t add yeast. Folks get wigged out by this single-celled organism, for one reason or another. But sourdough starter? It doesn’t need added yeast to create a starter that will give magnificent lift and flavor to your favorite breads. Say wha, no yeast?

Yeast is all around us in the environment, and it exists naturally in flour. If you’re a frequent baker of anything, you’ve got loads of yeast floating around your kitchen. But even if you’re not (like me), making a DIY sourdough starter is a piece of cake.

Or rather, a piece of pineapple.

While googling “Peter Reinhart” (a trusted master bread baker), I came across a really interesting article on modern flours and acidity. Without going too deeply into the science here (Mr. Reinhart explains it nicely in the article), yeast likes a slightly acid environment, and adding pineapple juice to your starter lifts acidity to yeast-lovin’ levels.

You don’t need pineapple juice to create a starter — plain ole flour and water will do it — but pineapple juice makes a quicker job of it. One common problem in making homemade wild yeast sourdough starter is the patience factor: flour + water + warmth will almost always make a successful starter, but there can be stretches of days when nothing’s happening, and it seems to the sourdough-starter-beginner that it’s failed, when actually, a few day’s wait and a little more flour will let the yeast catch up with expectations.

Pineapple juice keeps things moving along, with daily visible changes that keep the need for instant results at bay. (Don’t worry: the juice leaves absolutely no taste of pineapple in the finished product).

I documented my wild yeast sourdough with pineapple juice experiment (spoiler alert: it’s fabulous). Let’s take a look.

Starting with flour and pineapple juice to create a seed culture, Day 1 will be, essentially, a bowl of paste. No worries. Just cover lightly and place in a warm spot, stirring thoroughly twice within next 24 hours. By Day 2, you should see little bubbles on the surface — that’s happy yeast giving off carbon dioxide as a byproduct of its activities (don’t forget to stir twice — I make a point to stir at 8am and 8pm throughout this process).

On Day 3, add more flour and pineapple juice. When you stir, you’ll notice the seed culture to be very stretchy with gas bubbles forming easily. Take a sniff test: it should smell wonderfully sourdoughy and tangy. On Day 4, the seed culture will be bubbly and slightly foamy. Keep stirring, twice a day.

Day 5 means more feeding of the starter with flour and, this time, filtered water instead of juice. Overnight, the seed culture should double in volume and get foamy. If you look carefully at the bowls above, you can see how much further up the side of the bowl the seed culture is in the right photo than the left. Now we’re ready to create the starter on Day 7!

Mix together fresh flour and filtered water. Notice in the photo on the right how nice and stretchy the seed culture is.

Weigh out the appropriate amount of seed culture (you can toss the remainder, use it to make another starter, or share it). Incorporate it into the new flour/water mixture, and knead it briefly like bread dough.

And …

… voilà!

Sourdough starter.

Store in the fridge and feed regularly, and you’re all set. It’s living thing, so you’ll notice that it rises and collapses and bubbles throughout the week. Amazing. Wild yeast sourdough starter lasts years, decades even.

Why do you need a starter in the first place? In one word: flavor! The longer you leave any yeasted product to ferment – whether a starter or the bread dough itself – the more deeply flavorful your bread will be. A sourdough starter gives you a head start on building incredible flavor in your homemade bread.

Your starter will make all sorts of delicious breads, like sourdough flatbread, sourdough biscuits, and sourdough rye (which will be coming to a SoupAddict blog near you next week, along with a soup that was born to be sourdough rye’s BFF).

Bake on!

Karen xo

Tips for a great wild yeast sourdough starter:

» Yeast likes a little heat. I have a heating mat for my vegetable seedlings that keeps the ambient temperature at a perfect 70°. Works like a charm. Barring that, if you keep your house chilly in the winter like I do, you’ll have to get creative: check out your major appliances for little heat spots: on the top of the fridge, near a heating vent (but make sure it doesn’t get too hot).
» You’ll need 3 ounces of pineapple juice for this starter – canned pineapple juice is perfect. I’ve noticed that an 8 ounce can of pineapple chunks produces 3 ounces of juice: drain off the juice for the starter and eat the pineapples as a snack.
» If you have a scale, weigh everything, including the juice and water (the starter’s pretty forgiving, though)
» Don’t worry if your starter doesn’t follow the schedule exactly. Depending on the environment in your home, you might be off a day or two. But don’t give up — most starters will get into gear when the flour is added. If things are really pokey, and you’re okay with a harmless cheat, you can add a small pinch of instant yeast.
» This recipe makes a nice amount of starter. But, there are lots of different techniques and formulas that make varying amounts of starter — don’t hesitate to do some interwebs research to see what fits your needs best.
» Don’t forget to feed your wild yeast sourdough starter regularly. If you plan on baking bread often, keep it on your counter in a lightly covered crock or glass container, and feed it twice a day (I know!). If not, keep it in the refrigerator (lid not attached tightly) and feed it once per week (this is what I do, no matter my baking plans). My feeding process differs from the instructions below: I remove one cup of starter (and use or discard it), and mix in one cup of all-purpose flour to one scant cup of filtered water. Stir it up, give it a quick knead, and stick it back in the fridge.
» When handling the starter, wet your hands. I see many books (puzzlingly, even by the pros) telling you to flour your hands. A wild yeast sourdough starter is loose and wet – floured hands + wet starter = pasty hands. With wet hands, the starter will slide right off.

From a Peter Reinhart formula published on NYtimes.com. Note that I left the instructions largely intact with minor additions for clarity.