How to Fix an Overly Acidic Sourdough Starter

Your starter used to double happily, and now it barely creeps up, smells sharp enough to make your eyes water, and leaves your dough slack and sticky. If you are searching for how to fix acidic sourdough starter, this is usually the story: acid has quietly built up faster than the yeast can cope with, and the culture is out of balance — not finished.

The full walk-through is in our Sourdough Starter Troubleshooting guide — it works through look, smell, temperature, and feeding, one check at a time. Here is the reset in short.

Acid takes over when a starter spends too long hungry after its peak, or sits somewhere warm enough that fermentation races ahead of feeding. A modest feeding stirred into a lot of old, sharp starter barely dilutes anything, so each day begins more acidic than the last and the rise keeps getting weaker.

• Start the reset small. Keep just a spoonful of the starter and set the rest aside. That spoonful carries the culture you want to keep, without carrying over days of built-up acid with it.
• Feed it big. Give that small amount about five times its weight in fresh flour, and the same again in water, then mix it well. All that fresh food dilutes the acidity in one go and gives the yeast a clean table to work at.
• Repeat at the peak, not by the clock. Wait until it has risen as high as it will go and is only just starting to soften on top, then do the same small-keep, big-feed reset again. Two or three rounds like this usually turn a sharp, sluggish starter around.
• Hold its spot steady while you reset. Keep it comfortably warm but out of direct heat, and change nothing else — same flour, same routine — so you can actually see the acidity easing instead of guessing which change did it.

Judge the reset at the peak: a cleaner, gently tangy smell, plenty of bubbles, and a rise that holds instead of collapsing. When you see that, your starter is back in balance and ready to bake with again.

Prefer a Starter That Starts Balanced? Get Yours →

Can an overly acidic starter recover, or do I need a new one?

It almost always recovers. The yeast is still in there — it is just outnumbered. A few generous reset feedings shift the balance back, and starting over is rarely necessary.

How do I stop it turning acidic again?

Feed it before long hungry stretches, especially where it lives warm, and keep the amount you carry over modest. Small, regular attention beats an occasional rescue every time.

See the full reset in the troubleshooting guide →

Questions? Just message us — we'll get back to you, we promise. No AI chatbots here, just real people who bake sourdough every day.