Getting A Sourdough Starter Going
I have made dozens of starters over the years and there is really nothing mystical about it. It takes about a week and some flour and water sitting on your counter. The whole process is mostly waiting, but there are a few things that actually matter if you want something that will last. Mix together 50 grams of whole wheat flour and 50 grams of water in a quart jar. Stir until it looks like a thick paste. Cover it loosely with a lid or a cloth and leave it at room temperature. Do this every day for five to seven days. On day two or three you might see bubbles. On day four or five it should smell yeasty and slightly sour. By day six or seven it should double in volume within six to eight hours after feeding and pass the float test. The float test means dropping a small spoonful of starter into a glass of water. If it floats, it has enough trapped gas to be considered active. If it sinks, keep feeding it.
One thing most people get wrong is the flour choice. All-purpose white flour works, but it takes longer and produces a weaker starter. Whole wheat or rye flour has more wild yeast and bacteria on the bran, so it gets going faster. I use a 50-50 blend of bread flour and whole wheat myself because it gives consistent results without being too aggressive. I once had a starter that smelled like acetone nail polish remover from day three onward. That is not a sign of failure, it is a sign that the microbial balance was off and the lactic acid bacteria were dominating before the yeasts had a chance to establish. The workaround was simple. I fed it twice a day instead of once and kept the feeding ratio at one part starter to two parts flour and two parts water by weight. Within two days the smell shifted back to something fruity and tangy. That is how you know the yeasts have won. Here is a detail most guides skip: temperature matters more than timing. If your kitchen runs below 68°F the starter will crawl. It will still work, but fermentation slows and you may need eight or ten days before it is ready. If your kitchen is above 75°F it moves fast and you might need to feed it twice a day just to keep it from collapsing. The ideal range is between 72 and 76°F.
Another counter-intuitive thing is that a healthy starter does not always need to be fed twice daily once it is established. After the initial ten-day build, you can transition to a weekly fridge routine if you are not baking every day. Feed it, let it sit at room temperature for two hours, then put it in the fridge. When you want to use it, take it out, discard most of it, and feed it a couple times over the next day before baking. The biggest mistake beginners make is judging readiness by smell alone. Smell is subjective. The real indicators are volume increase, a dome shape at peak, and the float test. Some starters smell awful and are perfectly fine. Some smell great and still fail the float test because they have not developed enough gas retention structure. That structure comes from proper gluten development during mixing and consistent feeding ratios. I have also learned that using filtered water helps if your tap water has strong chlorine. Chlorine kills wild yeast and can delay colonization. If your water is heavily chlorinated, letting it sit out uncovered for an hour before mixing dissipates most of the chlorine. Bottled spring water works too, though it costs more.
When your starter is ready you can maintain it with equal parts flour and water by weight. A common ratio is 1:1:1, meaning one part starter, one part flour, one part water. For example, 25 grams starter, 25 grams flour, 25 grams water. Feed every twelve hours if keeping it on the counter, or once a week in the fridge. Weighing is important because volume measurements like cups are inconsistent and lead to starters that are either too thick or too runny. A runny starter is usually underfed or made with too much water relative to flour. A thick starter that cracks on top is often overfed or left too long at room temperature before refrigeration. Both are fixable by adjusting your ratios. If it is too runny, increase the flour by ten grams per feeding. If it is too stiff and cracking, add five grams more water next time. Do not expect perfection on the first attempt. Starter culture is a living organism and it changes based on your environment, your flour, and how often you use it. The goal is not a perfect recipe. The goal is a reliable one that you can feed and bake with without constant babysitting.
