MakeMyOwn.diy

How to make my own sourdough starter

Flour, water, a jar, and about a week of twice-daily feeds until it doubles on schedule.

Time
20 min
Difficulty
medium
Makes
1 active starter jar
Steps
6 steps

Updated Sep 6, 2026

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How to make my own sourdough starter

Starter is a wet flour culture you keep alive, not a packet of instant yeast. You are selecting wild yeast and bacteria that already live on grain and in your kitchen.

The only job for day one through seven is: mix, wait, discard, feed. Do not bake with it until it doubles in 4 to 8 hours after a feed and smells tangy, not like paint or vomit.

What you need

0/6

Step by step

  1. 01

    Day 1, morning: mix 50 g whole-grain flour and 50 g water in the jar. Scrape the walls. Cover loosely. Leave at 22–26 °C if you can.

  2. 02

    Day 2, morning: it may look sleepy. Stir, then add 50 g flour and 50 g water. Mark the height with the band.

  3. 03

    Day 3 onward, morning and night: discard down to 50 g of the mixture. Feed 50 g white flour and 50 g water. Stir until no dry pockets remain.

  4. 04

    If it hoists the band in 6 hours and is full of bubbles, you are close. If it never rises, the room is cold — move it to the oven with the light on, door cracked.

  5. 05

    When it doubles predictably twice in a row, it is ready for a loaf. Use it at peak, not after it has collapsed.

  6. 06

    For the fridge: feed, let it rise 1 hour, then cold-store. Feed at least once a week. Bring it out and give two room-temperature feeds before baking.

Notes

  • Pink, orange, or fuzzy growth is mold. Throw the jar contents out and start over. A dark hooch on top is hunger — pour it off and feed.
  • Discard is still flour paste. Cook it as pancakes; do not pour pounds of it down a slow drain.
  • Whole-grain at the start jump-starts activity. Switching to white later makes a milder, more predictable rise.

Questions people ask

Otherwise the jar becomes a sour ocean you cannot keep acidic enough. The remaining 50 g is plenty of culture.

Safety note: this is practical DIY guidance, not medical, chemical, or professional advice. Skip anything that feels unsafe for your setup.

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