The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Sourdough culture question: differing cultures

pattyfermenty's picture

Sourdough culture question: differing cultures

Let's say that I have a "special" culture, from Egypt or something, purchased from For months I feed it with King Arthur AP flour. Can someone who really knows their stuff please explain to me how my culture does not eventually become dominated by the yeast that is all over the King Arthur flour? Yeast don't kill other yeast, do they? That means that any yeast is free to eat food and propogate. It would seem to me that if you do have different strains competing over time, it is the strain which reproduces faster which will domanate over time. Anybody here really know their stuff on yeast that could comment? TIA!

alittlesquirrely's picture

Hello, I bought two different starters (from e-bay) and there was a definite odor difference in them after a few days. One smelled sweet/yeasty, the other a little more sour, but my inexperienced nose and palate could not tell the difference in the breads or pancakes I made. Now I read above that yeast from the air/flour added etc. can possibly "take over" your starter! Is there REALLY a difference in taste between starters, or is it just the age/development/type of water and other variables that is responsible for the taste difference (if any)??? Pattyfermente-I am picturing  "yeast wars and flour fights" in your frig!

plevee's picture

Hi, I bought 2 powdered starters several years ago. They activated quickly and initially had very different aromas, and the breads they raised had a pleasant unsour flavour which was different from those grown with my home grown starter, but not from each other.

Over the course of a few months, despite taking care not to intermingle them when feeding, they both came to smell and perform exactly like my home grown starter. I concluded that the organisms in the feeding flour simply overwhelmed those in the initial cultures.

It hadn't occurred to me that this might simply be due to aging. It would be interesting to split my current culture in half and feed  each different flour for a month or so to see if any difference in smell emerges. Perhaps I'll try it.


pattyfermenty's picture

i have had the same experience. nonetheless, you have sites like selling different cultures and telling people to feed those cultures with flour. well, flour has yeast in it. not much, but enough for me to start a raging culture in 4 days. so everytime i feed my culture, i am introducing yeast into it and these yeast, if given enough time, can propogate. it seems to me plainly that the yeast that reproduces faster takes over. is it possible that all these people who think they have separate cultures merely have the culture of the yeast contained in the flour that they feed their cultures with? hopefully someone who really knows about this can respond to this simple question: how can a culture maintain itself when their is yeast in the flour that it is fed everyday.

Pharnzworth's picture

I wonder if it would be possible to maintain the original yeast strain if you heated your "maintenance/feed" flour to, let's say, 120F (to kill the yeast residing on it) before feeding it to the starter.