What does feeding a sourdough starter actually do?

Feeding gives the wild yeast and LAB fresh sugars to eat, but its real job is dilution. Adding flour and water drops the acid level back down so the culture leaves its sour, sluggish state and starts producing gas again. You are not just topping up food. You are resetting the clock.

What is the best feeding ratio for a sourdough starter?

It depends on your timing, not your taste. A 1:1:1 ratio (equal parts starter, flour, water) peaks in 4 to 6 hours and suits same-day baking. A 1:5:5 ratio peaks in 8 to 12 hours and is ideal for overnight builds or stretching the time between feeds. Pick the ratio that matches your schedule.

Should I feed my starter by weight or by volume?

Always by weight, using a digital scale in grams. A cup of flour and a cup of water are wildly different weights, so volume feeding makes your hydration drift every time. Weight keeps the ratio honest and your starter predictable from one feed to the next.

How often should I feed my sourdough starter?

On the counter at room temperature, feed once or twice a day. In the fridge, once a week is enough because the cold slows the culture to a crawl. If you bake often, keep it warm and fed daily. If you bake rarely, the fridge is your friend.

Why do I have to discard sourdough starter before feeding?

Without discarding, the jar would double in size every feed and you would need ever more flour to keep the ratio. Discarding keeps the volume manageable and removes built-up acid that would otherwise weaken the culture. Save the discard for pancakes or crackers rather than binning it.

How to Feed a Sourdough Starter (Ratios, Timing)