Flavour & Fire
The Sourdough Journal
Feeding Your Starter
At its heart, feeding a starter is wonderfully simple: keep a portion of your existing starter and give it fresh flour and water. Before long, though, you will come across ratios such as 1:1:1, 1:2:2 and 1:4:4 — and naturally, you may wonder which one you are actually supposed to use.
The good news is that there is no magic ratio. What you are really doing is adjusting how quickly your starter becomes active and how long it takes to reach its peak. Feeding therefore becomes less of a fixed ritual and more of a way to make your starter fit the day ahead.
Why does a starter need feeding?
A starter lives on the nutrients in flour. As the microorganisms use those nutrients, the composition of the starter changes and it gradually becomes more acidic. Without fresh food, its activity will eventually slow down.
By keeping a portion of your starter and adding fresh flour and water, you give the culture a new supply of food. At the same time, you keep the amount manageable. If you simply kept adding more flour and water without ever removing any, your jar would soon become a rather impressive sourdough reservoir — and you would need a cupboard of its own.
Refreshing your starter also creates a new balance between the existing culture and its fresh food. That is where the different feeding ratios become useful.
Understanding the ratios
The numbers in a ratio such as 1:2:2 refer to starter : flour : water, measured by weight rather than volume. The ratio you choose mainly affects how quickly your starter moves through its feeding cycle.
1:1:1 — for example, 25 g starter + 25 g flour + 25 g water. You begin with a relatively large amount of existing starter and less fresh food. This means it becomes active quickly and may reach its peak within a few hours, depending on temperature and the condition of your starter.
1:2:2 — for example, 25 g starter + 50 g flour + 50 g water. This is a useful, versatile ratio for everyday maintenance. You give your starter noticeably more fresh food than with 1:1:1, so it will usually take a little longer to reach its peak.
1:4:4 — for example, 25 g starter + 100 g flour + 100 g water. Here, the existing starter receives considerably more fresh food. It therefore takes longer for the culture to work through its supply and reach its peak. This can be useful when you want to feed your starter well ahead of when you plan to use it.
So the ratio is not a rule you have to follow. Think of it more like a slider. If you want your starter to become active sooner, use relatively more existing starter. If you want to give it more time, give it relatively more fresh food.
Mother starter and baking starter
It helps to distinguish between your mother starter and your baking starter. Your mother starter is the small amount of culture you keep and maintain regularly. It is your base — the little jar that lives in your kitchen.
Your baking starter is built specifically for a recipe. You take a small amount from your mother starter and feed it enough flour and water to create exactly the amount your dough requires.
There is a practical advantage to working this way: you do not need to maintain a large jar of starter all the time. Your mother starter can stay small, while you build up exactly what you need for each bake. Less excess starter also means less flour going to waste.
How often should you feed it?
How often you feed your starter depends largely on where it lives and how active it is there.
At room temperature, a mature starter will usually need feeding once a day. In a warm kitchen, a starter fed at a lower ratio such as 1:1:1 may move through its food more quickly and need feeding twice a day. In a cooler room, the same starter may take considerably longer to complete its cycle.
In the fridge, fermentation slows dramatically. A mature starter can generally go about a week without feeding, sometimes longer. When you want to use it again, give it one or more feeds at room temperature to bring it back to full activity. For more on storing and reviving a starter, see Storing Your Starter.
The clock is only a guide
It is tempting to create a fixed routine — feed at eight every morning, feed again every evening. If that works for you, there is absolutely nothing wrong with it. But your starter has no idea what time it is.
The same 1:2:2 feeding may reach its peak much faster in a warm summer kitchen than in a cold winter one. The flour you use, the amount of starter you begin with and the activity of the culture all make a difference too.
Use timings as a guide, but learn to recognise your starter’s own rhythm. Bubbles, volume, aroma and the moment it begins to fall again all tell you where it is in its cycle. Learning to read your starter is ultimately more useful than memorising a schedule.
A few small habits
Keep your jar clean. Scrape down the sides after feeding, and switch to a clean jar when dried starter starts to build up around the rim. It makes your starter easier to keep an eye on and helps prevent old residue from becoming a source of unwanted growth.
Mix each feeding thoroughly. You want the flour and water evenly distributed throughout the existing starter, without dry pockets or lumps of flour. Once mixed, you can smooth the surface and mark the level so you can easily see how far it rises.
And do not be afraid to adjust your routine. A different flour, a change in temperature or a different feeding ratio can make your starter behave differently. That does not necessarily mean something is wrong. Watch what changes, give your starter a few feeds to settle into the new conditions, and let it show you what it needs.
Feed it, wait, and trust the rhythm more than the clock.