Your sourdough starter stinks. It smells like old gym socks. If you’re baking at home, that’s happened to you before: you followed some kind of schedule rather then paying any attention to biology of it all. To make sourdough, one has to mix together flour and water, taking account not only of the ratio (obviously), but also temperature, and timing of it all.
These factors gets broken down into parts in chart, but to know how they fit into big picture, you have to understand why numbers matter. Maintaining this equilibrium between the microbes and food they consume requires feeding your starter. Feeding it too little (in comparison to how much starter you’re maintaining) will result in a fast depletion of available starches and an outpouring of harsh acids. You’ll know your yeast are distressed when that unpleasant vinegar odor appears… Distress, not flavor.
How to Fix a Smelly Sourdough Starter
Feed it too much by diluting the existing culture with too much flour and water and the bacteria will be sparse and take ages to get moving. You want your starter to double before it becomes too acidic. You also don’t want it to sit inactive for days at a time.
Most bakers stick to a standard one-to-two-to-two ratio, meaning one part starter to two parts flour and two parts water by weight. Most bakers sticks to a standard one-to-two-to-two ratio because it provides enough food for a robust rise while keeping the acidity manageable. So why does this ratio work? Well, as you’ll see from the chart, it’s not so much about exact ratios, but about consistency.
A drier starter, one that requires less water, will be stiffer and take longer to peak but hold its shape well. In contrast, a wetter levain peaks sooner but may prove trickier to incorporate in the dough. Note how the hydration affects the rise-time in infographic. For greatest flavor depth, go easy on the hydration, meaning higher dilution ratios, for longer fermenting times. That lets the micro-organisms have time to realy dig into their meal without rushing them.
Experienced bakers get tripped up by something you can’t see: temperature. Your kitchen runs at seventy degrees? Your friend’s at eighty? It’ll behave very differently. Heat speeds up the enzymatic action in your dough, which could means your starter peaks in half the normal timeframe come summertime. So to track its rise, you need to go by what you see, using a rubber band to mark where it gets to as you work (you can’t bank on hours-of-the-day like a clock; that only works some of the time). Look for when it doubles and domes just a bit before deflating, then you’ve got it.
A helpful backup is float test, but more often than not, visual clues are clearest of all about how yeast and gas inside have formed. That’s why the answer isn’t usually “get rid of the culture” when things go awry: Dilute the acids by adding more flour and water if your starter gets too sour. Discard less of old starter and feed what remains. This way, there aren’t as many competitors to share a feast with. It also provides more food for yeast if it goes flat, even though you are keeping it fed.
It is less like strict rules and more like listening to what your jar tells you. At its heart, caring for a healthy sourdough starter isn’t realy so much math as it is tuning your gut. You need to learn to detect when the mixture is losing energy or how it feels different than when you have added too much or too little water; you will know by feel.
That’s the beauty of it, a little ritual each day that will pay off with each loaf of bread baked. Just heed this reminder: be sure to use water at room temperature (too hot or cold, and you run the risk of shocking the yeast to death or slowing them down). Trust your instincts rather than your watch, keep your observations close, and let the bubble show you the way.
You should of listened to your starter earlier.