Your First Starter

What this is about

In ten days, flour and water turn into a starter: the living dough that will later raise your bread and give it its sour taste. You need nothing store-bought and no additives, only patience. From day 4 on, the mixture looks like it has failed, and that is exactly when it works hardest.

How to do it

You need a straight-sided clear glass jar with a loose lid, a rubber band as a marker, a scale, a thermometer, and whole rye flour. Rye starts fastest and most reliably. Use flour and water in equal parts. Keep the jar at 27 °C; read the temperature at the jar, not at whatever warms it. Tap water is fine.

1. Day 1: Stir 50 g whole rye flour and 50 g water (35 to 40 °C warm) until smooth. Slide the rubber band to the height of the mixture, so you can see later how far it has risen. Rest the lid on loosely so the gas can escape, and put the jar in a warm spot.
2. Days 2 and 3: Stir vigorously twice a day, but do not feed. Note the bubbles and the smell.
3. Day 4: First feeding, even if nothing seems to be happening. Keep 40 g of the mixture, discard the rest, and add 40 g whole rye flour and 40 g water.
4. Days 5 and 6: Feed once a day at the same time, with the same amounts as on day 4.
5. From day 7: Feed when the dome falls back after its peak, usually twice a day: 40 g mixture, 40 g flour, 40 g water.
6. Day 10: Check whether the starter is ready (see below). If not, carry on in the same rhythm.

Discard first, then feed. Throwing away most of it each time is part of the process; it keeps the amount small. Put the discard from the first days in the trash, not in the oven.

How you know it is right

On days 2 and 3, the mixture foams and smells unpleasant. That is theater: yeasts make gas, bacteria make acid, and at the start the wrong bacteria arrive first and produce the gas. On days 4 to 6 it stands still and smells like cheese or nail polish remover; this is where most people give up, but you don't, because inside the jar the acid is building up. From day 7 on, it rises steadily after every feeding, domes, and smells mildly sour, yeasty, and like yogurt.

The starter is ready for baking when it doubles three times in a row within four to eight hours and smells pleasantly sour. What matters is the short time to the peak, not the height: rye rises flat and is strong anyway. After that, feed it daily for two weeks, then bake. From day 1, write down when you fed it, how warm the jar was, and how long the starter took to reach its peak. That time is the measure of its strength, and you will need it on baking day.

Mold means throw it out: fuzzy spots in pink, orange, gray, or black, or a rotten smell. Clean the jar thoroughly and start over. Almost everything else only means the starter is hungry, for example gray liquid on top or a sharp smell: pour the liquid off and feed.

Rules to remember

• Use whole rye flour, a jar with a loose lid, and 27 °C at the jar.
• Day 2 is theater, day 4 is hidden work. Do not give up, and do not feed before the peak.
• Ready for baking means repeatable: doubled three times in a row within four to eight hours.

In the Pro edition: wheat and lievito madre starters, why the pause comes, the reserve on day 4, converting to a different flour, and the most common mistakes and how to fix them.