How to Keep a Sourdough Starter Healthy and Active
A healthy sourdough starter does not need to bubble furiously all day, and a starter that looks flat is not necessarily dead.
What matters is whether it responds predictably after feeding.
Feed it, keep it at a suitable temperature, and watch what happens. A healthy starter should rise, develop bubbles and eventually fall again as it uses up its food.
Once you understand that cycle, looking after a starter becomes much less complicated.
First: Is a Flat Starter Actually a Problem?
Not always.
A starter can look flat because it has not started rising yet, because it has already risen and fallen, or because it has been sitting cold in the fridge.
Look at the jar rather than the surface alone.
You may see streaks higher up the sides showing that the starter previously rose and then collapsed. You might also see small bubbles throughout the mixture even though the top looks fairly quiet.
If you are unsure, give it a normal feed and watch what it does next.
That tells you much more than one glance at the jar.
Choose a Routine That Matches How Often You Bake
You do not need to keep your starter on the kitchen bench forever.
If you bake frequently, keeping it at room temperature can make sense because it stays active and ready for regular use.
If you only bake occasionally, the fridge is usually much easier. The cold slows fermentation, so the starter needs far less attention.
| Your Baking Routine | A Practical Starter Routine |
|---|---|
| Baking frequently | Keep it at room temperature and feed it regularly |
| Baking occasionally | Keep it in the fridge between bakes |
| Taking a long break | Consider drying a small backup |
The best routine is the one you can actually maintain.
What Does a 1:1:1 Feeding Mean?
Starter feeding ratios are usually written as:
starter : flour : water
So a 1:1:1 feed could be:
- 20g starter
- 20g flour
- 20g water
It is a simple place to start, but it is not the only correct way to feed a starter.
A higher feeding ratio gives a smaller amount of existing starter more fresh flour and water. That usually means it takes longer to work through its food.
Different bakers use different ratios depending on temperature, feeding frequency and the starter they are maintaining.
If your current routine works reliably, there is no reason to change the ratio simply because someone online uses a different one.
Why Do We Remove Starter Before Feeding?
Mainly because otherwise the amount grows very quickly.
If you kept all of yesterday's starter and added another equal quantity of flour and water every time, you would soon need a very large jar and a lot of flour.
Keeping only a small amount makes the starter easier and less wasteful to maintain.
The portion you remove does not necessarily need to go in the bin. Once your starter is established, it can be kept as sourdough discard and used in recipes designed for it.
Learn the Rise and Fall
After feeding, a starter usually goes through a recognisable cycle.
At first, there may not be much happening. Then bubbles appear and the starter begins to expand.
Eventually it reaches its highest point. Later, it begins to fall again.
A rubber band around the jar at the level immediately after feeding makes this much easier to see.
Do not worry if your starter does not behave according to somebody else's exact timetable. Temperature, flour, feeding ratio and the condition of the starter all affect how quickly it moves.
What you want is repeatable behaviour.
Temperature Changes the Speed
A warm starter generally ferments faster. A cool starter generally takes longer.
This is why a starter that seems extremely active in summer may suddenly take much longer to rise during a cold New Zealand winter.
If yours is healthy but moving slowly, giving it a comfortably warmer place may be all it needs.
If it races through a feeding and collapses long before you are ready to use it, a cooler location or a different feeding schedule may be more useful.
You do not need to chase one exact temperature. Pay attention to how your starter behaves in your kitchen.
Do You Need Filtered Water?
Usually, no.
If your normal tap water is suitable to drink and does not have an unusually strong chlorine smell, it will generally be fine for maintaining a sourdough starter.
If your starter is struggling and your water smells strongly treated, then trying filtered water is a reasonable troubleshooting step.
There is no need to buy bottled water automatically just because you make sourdough.
What Flour Should You Feed It?
A mature starter can be maintained successfully with different flours.
The easiest approach is usually to choose a flour and keep the routine reasonably consistent.
If a neglected starter is particularly sluggish, replacing a small portion of the feeding flour with wholemeal or rye flour can sometimes encourage more activity.
But again, do not change flour every time the starter has one slow day. Temperature or timing may explain it just as easily.
What Kind of Jar Should You Use?
A clear container is useful because you can easily see bubbles and how far the starter has risen.
Leave enough space above the starter for it to expand.
Use a lid to stop the surface drying out and help keep unwanted material out of the jar, but do not tightly pressure-seal an actively fermenting starter.
You also do not need to transfer it into a sparkling new jar every day.
Keep the jar reasonably clean, especially around the rim, and change or clean it when build-up becomes inconvenient.
What Is the Liquid on Top?
A neglected starter sometimes develops a grey, brownish or dark liquid on top, often called hooch.
That does not automatically mean the starter needs to be thrown away.
It is commonly seen when starter has been left for a long time without feeding, particularly in the fridge.
You can pour the liquid off or stir it back in, then give the starter a fresh feed and see how it responds.
When Should You Throw a Starter Away?
Some unpleasant smells and appearances can happen when a starter is hungry, so not every odd-looking jar is ruined.
There are, however, signs that should not be ignored.
Discard the starter if you see:
- visible mould
- pink or orange colouring or streaks
- clearly abnormal coloured growth
- a genuinely rotten or putrid smell
Do not simply scrape visible mould from the top and continue using what is underneath.
How Do You Know a Starter Is Ready for Bread?
Do not judge it from a few bubbles.
A starter you plan to rely on for bread should be rising strongly and predictably after feeding.
You are looking for:
- a clear increase in volume
- bubbles throughout the starter
- a light, aerated texture
- a clean fermented smell
- similar performance over repeated feedings
If a starter has just come out of a long stay in the fridge, it may need more than one feeding before it returns to its usual strength.
Let its behaviour tell you when it has recovered.
If Your Starter Is Sluggish, Keep the Fix Simple
Before changing everything, check the obvious things.
- Has it been fed recently?
- Is your kitchen unusually cold?
- Has it been neglected in the fridge for a long time?
- Are you giving it enough time to respond after feeding?
Give it a few consistent feeds in a comfortably warm place and watch for improvement.
A little wholemeal or rye flour can also be useful for a sluggish starter.
What you usually do not need is five new feeding ratios, bottled water, a special jar and an expensive warming gadget all on the same day.
A Healthy Starter Should Make Your Life Easier
You do not need to keep a sourdough starter at peak activity every hour of every day.
Learn how yours normally rises and falls, keep it in the fridge when you are not baking regularly, and give it time to become active again when you need it.
And if you have maintained the same starter for a long time, dry a small amount as a backup.
Most importantly, remember that one quiet starter does not automatically explain one flat loaf. The starter is only one part of fermentation.
Look after it well — but do not blame the jar for everything that happens to the bread.