I gathered below the answers to some of the most common questions related to ‘How to maintain a sourdough starter’
For a full Q&A on how to care for your sourdough starter, check my Sourdough Starter guide. It also includes guidance on how to ‘Make a sourdough starter from scratch’

Should I buy a sourdough starter or make my own?

If you want to take on the challenge, then I would say to try and make your own. Making a starter from scratch can take anything between 5 days and couple of weeks. So if you’re patient enough, then go for it.

Otherwise, if you want to get straight into baking, buy one or ask a local bakery to give you some.

I don’t have a sourdough starter

You can make one from scratch, check this article of mine. If you’re in the UK, I am happy to post some dry starter, alongside instructions on how to activate it. I don’t charge for the starter itself, only for the postage (via RoyalMail). Get in touch.

Can I keep the starter on the counter?

Yes you can, but this means regular daily feeds.

If you bake daily, keeping the starter on the counter makes sense, however please remember that it requires 2 feeds a day, morning and evening. Recommended feeding ratio 1:4:4 or even 1:5:5. Feeding it only once a day, or in a low feeding ratio can lead to an over fermented starter. And it’s not only the flavour/odour that will be rather sour, but also the wild yeast activity is compromised.

If you bake couple of times a week or once a week, best to move the starter in the fridge. You would then remove it from the fridge for feeding ahead of preparing the dough.

Can I leave my starter out overnight after feeding it?

Yes, if you have just fed it. Since the night is rather long, feed it in a 1:4:4 ratio so that’s not over fermented by the morning. If for example you use a 1:1:1 ratio, the starter would have peaked in the middle of the night, and collapse by the morning.

If I keep the starter in the fridge, do I need to feed it before returning it to the fridge?

No, that should not be needed. You can just return to the fridge what’s left after you’ve used the amount you needed to prepare the dough.

Say you had 150g of starter in your jar at the fermentation peak, and you have used 100g to make the dough. You can just return the 50g back to the fridge.

However, if you have very little left, say 10-15g and you plan it to leave it unfed for longer than a week, I would advise to give it a feed, let it ferment on the counter, before returning it to the fridge.

What does the feeding ratio mean?

This is the ratio between the starter you carryover and the water and flour you use for feeding.

1:1:1 = 1 part starter to 1 part water to 1 part flour = equal quantities of each

What is the best feeding ratio?

There is no such thing as the best feeding ratio, it’s what works best for your schedule. Couple of rules for guidance though

🌾The lower the feeding ratio, the quicker it will ferment. A feeding ratio of 1:1:1 (equal quantities of starter, water & flour) is a lower ratio to 1:4:4 (1 qty starter to 4 quantities of water to 4 quantities of flour). Keep this in mind when planning. In essence the less starter you use compared to the amount of ‘food’ you give it, the longer it will take to finish it.

🌾The warmer in your kitchen, the quicker it will ferment (yeast loves warm environments). And the other way around. With the same feeding ratio, let’s say a 1:4:4, your starter can peak in 4-5h in summertime or in 7-8h in winter time.

🌾The type of flour you feed your starter with will also impact fermentation speed – the richer in enzymes (e.g wholemeal vs bread / strong white flour), the faster it will ferment.

If you feed your starter with less water to the amount of flour, which will result in a stiffer starter, the fermentation will be slower than when it’s fed to the same quantity of water and flour. Yeasts and bacteria don’t only love warm, but also humid environments.

🌾If you want to keep your starter on the counter, I advise you feed it every 12h, possibly in a ratio of 1:4:4 /1:5:5. However if you don’t bake daily, I would advise to store the starter in the fridge to avoid as much as you can waste.

How soon after feeding the starter can I use it?

It depends on the room temperature, and of course on the feeding ratio. Best to wait for it to reach its fermentation peak, rather than use time as the only way to assess it. It can take anything from 4-5h to 8-10h.

How do I recognise the starter has reached its peak?

It’s the moment when the starter stops rising in volume, its surface becomes wavy. After this point, it will start losing volume/sinking down. That’s your visual cue that the starter is ready to be used. If you cannot use your starter right then, pop it in the fridge instead until you’re ready to prepare the dough. You can even use it next day, without an additional feed (as long as it’s not overly sour in odour and collapsed to initial level).

Not all starters will show this sign, but most will do. This video will help you visualise it.

What if I go on holiday? Can I live the starter in the fridge for longer?

The day before your departure, give your starter one last feed.

🌾Use less water than the amount of flour, as this will help slow down the fermentation. For example a 1:3:4 ratio (10g starter : 30g water : 40g flour) can work well, you can even go for a 1:2:4 ratio. Please be aware that the starter will be stiffer than when using equal amounts of water and flour, and you might need to give it a light knead in a bowl or even on the counter, before placing it back in the jar.

🌾Leave the on the counter for 3-4h, for the fermentation to kick in. You want to see some movement. You can then move it to the fridge

🌾Let the lid loose, as fermentation will continue in the fridge, and the yeast will produce gas. You don’t want a mini burst when you open the jar

🌾Keep it far from any food that can grow mould on (fruit, veggies, cheese). Mould is the no 1 enemy of your starter, not the fact that’s left unfed in the fridge

🌾When you’re back, take it out of the fridge and give it 2 consecutive feeds before using it again. You can go back to your normal feeding ratio and routine.

🌾If any hooch has built up, remove that before feeding it, to help reduce its acidity quicker.

🌾If you’re planning to take a longer break from baking, I would dry some starter (spread it thinly on a parchment paper and let it dry at room temperature). Once completely dried, move it to an airtight container and place it either in the cupboard or freezer.

What is sourdough discard?

Discard is a part of your sourdough starter that is removed at every feeding, before adding water and flour. Since I believe in the power of example, here is one. Let’s assume you now have 120g starter in your jar, but you only want to feed 40g. The rest, 80g, is the excess that is being discarded. Discarding some of your culture is inevitable, otherwise you will be building an enormous amount of starter, as you’ll be adding water and flour at every feeding. And it’s not only that you’ll have a lot of starter, but the more it’s building up, the more acidic it will be. And this can compromise the development of your starter, but also its level of activity and leavening strength once you get to make bread with.

Do I have to discard every day?

First of all, you don’t have to feed it every day, unless you bake every day and you keep it on the counter. Otherwise, move it to the fridge.

But if you feed your starter every day, then yes, you have to discard every day, otherwise you will end up with an unmanageable amount of starter. Not only this, but also the starter will start becoming more and more acidic. The discard should not be fed again

What to do with the sourdough discard?

In reality the discard is a mixture of water & flour that has fermented. It can be used in any recipe calling for water and flour, replacing that with sourdough discard. Don’t let your discard sit in the fridge for too long, as it will become more and more acidic/sour over time. Which will affect the flavour of the baked goods.

If your discard is couple of days old, since it will still have some leavening power, you can even use it to make a sourdough focaccia. If your discard is older, the easiest is to use it for crackers. Here are some recipes you may want to try out.

If you don’t fancy extra baking, you may consider drying the discard, grinding it to powder and use it instead of rice flour for shaping, dusting the working surface & the dough. Check this video

How to feed my starter?

I have detailed everything about how to feed your starter in this article.

How to dry my starter?

I’ve tackled the topic in this article, including how to revive dehydrated starter

Can I use a different flour for feeding if I run out of the flour I normally use?

Absolutely yes,  this won’t be a problem. Any flour that you would use for baking, it can also be used to feed your starter. You can go back to your flour as soon as you get some of it. Or you might actually notice your starter is much happier with the new one. You can never know.

My starter does not pass the float test, should I be worried?

While the float test is widely used to test sourdough starter readiness, it’s not 100% the case that it will float. A rye starter which doesn’t trap as much gas as a white wheat starter, may never float. And this doesn’t mean it can’t be used and you won’t make great loaves with it.

The same for a young starter. It may not float, but be super bubbly and rise in volume for 3-4 consecutive feeds. Be confident, and give it a go. Other than the float test, there are other signs that your starter is healthy. Lots of bubbles, increase in volume, sour smell and flavour, aerated consistency.

My starter smells quite acidic, almost like nail polish. What does this mean?

This is quite normal for a starter that’s over fermented. Make sure you feed it often enough, but also that you give it enough food (flour & water). Avoid if you can a 1:1:1 feeding ratio

How long can I leave my starter unfed?

The sourdough starters are quite resilient, and can be left unfed, but in the fridge, for quite a long time. The longest I’ve left mine was for 8wks. Lid loose.

A dark watery layer, called ‘hooch’ (see this video) will appear on its surface, but that’s absolutely normal – it doesn’t mean your starter has died. This is just a sign that your starter has over fermented.

Just remove the hooch before you feed your starter again. You can also stir it in if the layer of hooch is rather thin, however bear in mind that it might take longer (more feeds) to reduce the acidity of your starter. I always remove it. It will require at least 2 feeds.

Move some starter to a clean jar and feed in a 1:4:4 ratio to drop acidity quicker (vs if you were to use a 1:1:1 ratio for example). You can feed as little as 10g if you want to use as little flour.

For example the first feed can be 10g starter + 40g water + 40g flour. For the second one (if you plan to prep dough with) you can increase the amount of starter you feed to the amount you need, to make sure you have enough for dough prep & a little extra at the end. 15g starter + 60g water + 60g flour, will give you enough to make a dough (100g), plus enough carryover to the next feed

How do I know I’ve killed my starter?

If you discover mold on your starter, there is no way around it and you’ll have to bin it. Consuming mouldy food can cause illnesses, and you don’t want to mess around with these things. I am no expert in the consequences of this, but I would not advise trying to revive your starter. Once it’s contaminated, there is no turn around.

Mold can show up in different colours (green, grey, black), usually fuzzy in appearance. Pinkish streaks are the signs of bad bacteria that has contaminated your starter.

Young starters are more likely to develop mould if unfed for a longer period of time. Their defence system is not yet fully developed as it is for a mature healthy starter. The good bacteria which is more resistant to contamination is not yet fully developed. If your starter is young, try to not leave it for too long unfed.