Converting bread recipes from commercial yeast to sourdough (wild yeast)

20 March 2010
By

This post originally appeared on the Cooking Manager blog as a guest post back in early February of this year, Cooking Manager is run by Hannah Katsman whom I first met over on Twitter. Cooking Manager has a lot of good, useful information, so check it out! 🙂


I’m not a long-time sourdough baker – I’ve only been baking sourdough (wild yeast) bread for the last couple of years. Since I don’t digest commercial-yeasted bread well, I use sourdough exclusively, which also means trial and error in converting recipes to sourdough.

butt ugly sweet bread, Sri LankaOne of my first breads was a sweet bread that I regularly made for breakfast. Problem was, while it tasted great, it didn’t consistently rise, even after 12 hours. Plus, even on occasions when it rose, it looked butt ugly. What was going wrong?

Turns out I was using too much sourdough starter in my bread recipe. After much research, I learned that a good amount of sourdough starter is about 10 to 20% of the flour weight in fermented flour.

Since I know that’s going to be confusing, let me use an example with easy math. I like easy math. 🙂

Let’s say you use this recipe to make bread:

  • 1000 grams flour (about 10 cups, depending on how you measure flour)
  • 650 grams water (2 3/4 cups)
  • 20 grams salt (4 teaspoons)
  • 2 packages dry yeast

And let’s say your sourdough starter is 100% hydration (that is, a 1:1 ratio of flour to water by weight), then, with a 20% fermented flour target in mind, I would use this:

  • 800 grams flour (1000-200, since I want 20% or 200 grams of the flour to be fermented in the sourdough starter)
  • 450 grams water (650-200 because the starter is equal amounts of water and flour)
  • 400 grams sourdough starter (200 grams flour + 200 grams water)
  • 20 grams salt

You can use less sourdough starter than 10% fermented flour for sure. It’ll take longer to rise, which is a benefit to some people, like if you want the bread to be more sour. But in most cases, I wouldn’t use more than 20%. I say most because I do have a recipe or two where I do exceed the 20% by quite a bit, but those are the exception, not the rule.

What happened to my butt ugly sweet bread when I reduced the fermented flour amount from about 26% fermented flour down to around 12% fermented flour? Ugly old lady butt dimples disappeared, and instead, I had smooth, lovely bread. And it rose! Consistently! Every single time!

butt ugly sweet bread, Sri Lankabutt ugly sweet bread, Sri LankaAnd my husband sang to me, “Baby butt, baby butt, baby butt buns, oh gimme my baby butt, baby butt, baby butt buns…” But he’s a little crazy. 😀

I’m sure the question “Why 20%?” must be occurring to someone. I asked it, too.

If you use too much sourdough starter in the bread, then there isn’t enough food from the fresh flour for the wild yeast to feed on. With insufficient food to feed on, the bread doesn’t rise since live yeast produces carbon dioxide as a biproduct, and what’s what gives bread its air holes.

As well, fermented flour has gluten that’s been overdeveloped (gluten develops naturally when flour becomes wet), which isn’t a problem when the fermented flour is used at low amounts, but when a lot of fermented flour is used, it can’t support the dough properly, hence the ugly dimples and inability to rise.

Tags: , , ,

3 Responses

  1. Thank you for the kind words and your excellent post.
    -Hannah

  2. #2
    Chanthru 

    Hi!
    You blog is interesting.
    I am from Sri Lanka.
    I want to know ordinary Sri lankan bread and buns are sourdough?

  3. #3
    Laurie 

    Hi Chanthru!

    My best guess is that breads/buns made in Sri Lanka is NOT made with sourdough, but instead is made with commercial yeast. Commercial yeast rises faster and gives more predictable results than sourdough, so sourdough would mean potentially higher costs involved for the bakery. This is true of bakeries worldwide. If it’s made with sourdough, then it’s usually labelled as such, and I’ve never seen such a label here.

    My suggestions, if you want sourdough bread, is to make your own. It’s not that difficult. 🙂

Leave a Reply

About LMAshton

Howdy and welcome to my site! I'm Laurie and I'll be your, er, hostess today. :)

I'm a Canadian expat currently living in Singapore. I'm married to a Sri Lankan and lived in Sri Lanka for nearly a decade. We also lived in New Zealand for half a year.

I cook Sri Lankan curries, sambols, and mallungs. I bake bread using wild yeast (sourdough that isn't sour). I bake on the stove. I experiment with Indian / Malaysian / Indonesian / Thai / whatever cuisines interest me. And I experiment wildly.

Life is an adventure. Join me! :)

If you want to know more about me, click on the "About" link in the navigation bar above. :)