Name: Create a DIY sourdough starter from scratch with rye flour
Prep time: 10 min
Total time: 10 min
Yield: 1 jar
Ingredients: 0.833 cup whole rye flour; 0.5 cup filtered water, 78-80°F; 0.417 cup whole rye flour; 0.417 cup all-purpose flour; 0.417 cup filtered water

Build a wild-yeast starter from nothing but flour and water in about 7-14 days. Whole rye flour is the best starting flour because its higher enzyme activity and free sugars give wild yeast and bacteria a fast, reliable environment to thrive.

Instructions

Day 1 — Mix: Combine 100 g whole rye flour and 125 g filtered water (78-80°F) in a clean glass jar. Stir vigorously, cover loosely, and mark the level with a rubber band.
Day 2 — Wait: Little to no activity is normal. Do not feed. Let it rest another 24 hr.
Day 3 — First feed: Discard all but 75 g. Add 50 g rye flour, 50 g all-purpose flour, and 100 g water. Stir and cover.
Days 4-6 — Twice daily feeds: Discard to 75 g every 12 hr. Feed with 50 g rye, 50 g all-purpose, and 100 g water each time. Activity may dip on Day 4-5 — this is normal as beneficial bacteria take over from the early Leuconostoc.
Days 7-14 — Build strength: Switch to a 1:5:5 ratio — discard to 20 g, add 50 g flour blend and 100 g water. Continue twice daily until the starter reliably doubles in 6-8 hr.

Tips

Use filtered or dechlorinated water — chlorine inhibits beneficial bacteria.
Keep the jar in a warm spot, ideally 75-80°F. Below 70°F, fermentation slows dramatically.
A digital kitchen scale is essential — volume measurements are too inconsistent for starter feeding.
The starter is ready when it doubles predictably, has bubbles throughout, a domed top at peak, and smells pleasantly tangy.
Any fuzzy mold (pink, orange, blue, green) means discard everything and start over.
You will go through roughly 500 g whole rye and 400 g all-purpose flour across the full 14 days.

Create a DIY sourdough starter from scratch with rye flour

Instructions

Tips

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