Keep the acid loving lactobacillus in balance with the wild yeasts by not letting your starter get too sour. Too sour means the yeasts won’t thrive and your bread won’t rise very well.
A starter gets too sour by not feeding it the sugars that live within the grains often enough.
Side Note Both lactobacillus and exguous yeasts eat plenty of things besides grain. They want simple sugars and can get them from legumes and starches, just as well as grains. Many traditional flat breads are made from only legumes, like Italian Socca, made with chickpeas, or some Indian Dosa types.
Both the yeasts and bacteria need food and warmth to thrive. Slow down fermentation for your starters by keeping them cold. They will continue to feed, but much more slowly, so you won’t have to feed them as often.
A firm starter ferments more slowly than a liquid one. Keeping a firm starter decreases the need to feed it so often. There is no need to keep a starter on your counter, slow it down and refrigerate it.
Speed up bread fermentation by keeping it at room temperature.
Develop flavor during the fermentation time, not proofing time. Fermentation can be slower, at a cooler temp. 65-75F or even in the fridge at 45F
A bread made with an active starter should never take long to proof. Give it warmth 85F and it should be up to size within one and a half to two hours max. If not then your starter isn’t active enough or proofing temperature was too low.
What's wrong with my starter?
So, I was at this party awhile back, this guy comes over and strikes up a bread conversation. As he launches off, I flash on how life has changed, where guys want to talk bread instead of books. He tells me "I’m a genius" if I can figure out what’s wrong with his sourdough starter.
“ I mix up my starter with the flour the night before right, but by the next morning it’s not bubbling much, and takes forever to rise. What’s going on?”
“ Is it really sour?”
“It, is, quite sour, yes, and it keeps getting sourer. Is there something I can do about that, feed it something?”
“ No, you can’t really back it up and make it less sour at this point, you’ll have to start over.”
“Really?-- No! Uh, I don’t know if I remember how to do that, but what happened, so I don’t mess it up again?”
He’s really into his starter, so I bend his ear a little.
“Sourdough starter is thick with wild yeasts and lactic acid producing bacteria that take up housekeeping together. The lactobacillus are what give the bread its complex slightly sour taste, while both the yeasts and bacteria eat the natural sugars in the grain and give off carbon dioxide, which creates bubbles in the dough, which causes it to rise.”
“Wow, I didn’t really know this any of this, besides the fact that sourdoughs are made with wild yeasts”
“ The cool thing about these particular wild yeasts that we bake sourdoughs with, mainly the yeasty with the name: Exi-gu-ous. Full name: Sac-charo-myces Exi-gu-ous. (My botany professor always said, “Just say it fast like you own it.”) is that they can tolerate acidity and still survive, but only to a point. The other yeast that we bake with, commercial yeast, is also a wild yeast that lives primarily on vegetable and fruit skins. It’s name is Saccharomyces cerevisiae, but don’t get me off track.”
“ So I let it get too acid and the yeasts are having a hard time fighting it out?”
“ That’s right. If a sourdough is not frequently fed the food the yeasts need, which are the natural sugars in the grain, then the lactobacillus will begin to dominate, and the yeast’s power to leaven will decrease dramatically as they struggle to survive, and it’s hard to turn it around and that point.”
“This is making sense. I didn’t use it or feed it for awhile and it got too sour. So the yeasts couldn’t thrive, this makes so much more sense to me, but why not just add some commercial yeast to the brew?”
“Because, cerevisiae yeasts ( the commercial yeast variety) are even less acid tolerant than exiguous yeasts (wild yeasts). They don’t live well with the lactobacillus, they can to a point, but not nearly as well as exiguous yeasts. That’s why sourdough is so good for you, all that lactobacillus probiotic action helps to predigest your bread, and create enough acidity for phytase to open up the doors to the mineral stores in the grain, and let the yeasts leaven your bread to boot.”
But, his attention is wandering. He sees his wife and hurries over to tell her how I’ve solved his sourdough mystery, calling me a genius. Pretty low stakes for genius status. Books and bread anyone?