Think of your sourdough starter not just as an ingredient but as a living culture. To keep it alive and kicking, it needs regular attention. Let it languish too long without food, and the culture will turn rancid and smell funky. It won’t even be able to get up and do its job, leavening the dough. The primary reason why most people starts and stop sourdough is irregular feeding habits.
The solution is to have a process in place for tending to your culture. The cardinal rule of maintenance: Discard most of the old starter and keep only a small portion, maybe twenty grams. At least most of it; that’s what will explode during the night if you don’t. Without discarding, acidity accumulate until your culture collapses. Hold on to a couple dozen grams in the jar (before topping off with fresh food).
How to Keep Your Sourdough Starter Healthy
By the way, add equal weights of water and flour. This ensures correct hydration. Scoop-and-pour doesn’t work since flour is uneven this way. And, yes, you want filtered water as chlorine will kill bacteria you’re trying to grow.
Depending on the warmth of your kitchen, it will take different amounts of time for fermentation. Typically, you’ll want about 6-8 hours at seventy-five degrees using a one:2:2 ratio (one part starter, two parts flour, and two parts water), though warm kitchens can accelerates fermentation to as little as four hours. This means when you come back to it, it’s doubled in volume, looking like a dome with lots of bubbles.
If your kitchen is warmer, fermentation occurs faster… Sometimes as fast as four hours for peak. Your cooler kitchen will make things go slower, much slower. To compensate, just change your feed ratio accordingly. If your kitchen is warm, and you don’t bake often, then use more flour and water compared to starter; if your kitchen is cool, do the opposite.
Many bakers don’t know how their choice of flour impacts culture’s health. Although all-purpose is fine, bread flour provides a stronger gluten structure so that it rises well. More nutrient-dense flours like rye and whole wheat also has wild yeasts, and can revitalize an overworked starter. When your starter doesn’t bubble any longer and looks tired, try feeding with whole wheat for a few times. The bran helps fertilize the microorganisms. Sometimes this little adjustment will save a culture on the verge of giving up rather than discarding it.
A good starter will have a pleasant scent (somewhere between yogurt and yeast). Anything that smells like rotting garbage/acetone is bad news. To double check whether your starter is fit-for-baking, you can perform a float test: drop a spoonful of starter into a bowl of water. Floats? It’s gassed up and primed for baking. Sinks? Give it more time. See some hooch on top? No worries, it’s just hungry yeast making alcohol. Stir it back in or pour it off, then feed. Orange or pink speckles are no bueno; dump those jars out.
When you’re not using it for baking, store your starter in the fridge. Once a week is enough to feed it and keep it alive while its life processes slows down during the cooler temperatures. Two days before you want to bake, take the starter out of the fridge. Reactivate by feeding it twice at room temp. Have a back-up portion dried on parchment just in case.
Working with wild yeast takes time and attention. Get to know the feeding rhythm. Pay attention to temperature changes. Let the starter do its thing, and result will be good bread.