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Troubleshooting: Sourdough Starters
Information by Julia Georgallis / Image of yeast by
The term 'sourdough' simply means bread made with a natural yeast, also called a sourdough starter, rather than fresh or dried yeast which comes from a packet. A shortage in packet yeast during the COVID-19 pandemic, plus a need for keeping hands and minds occupied turned many people onto sourdough bread - but maintaining a sourdough starter can be tricky! If my starter has taught me anything, it’s not to give up. It has been a friend of mine for the last six years, the pet that lives in the back of my fridge. More complicated than just making a cake, you are actively looking after something if you keep a sourdough starter, just like a plant, but a plant that you can put to bed in the fridge. But, I was very daunted when I began making my own sourdough and still get a lot of questions from people who are having teething problems with their tiny lactobacillus empires... I have pooled the most common queries using over 6 years knowledge of keeping and maintaining a sourdough yeast culture - I hope it helps… Feel free to comment below if you want to ask more questions.
How to make a yeast starter
USE IF: You don’t have a starter and want to make one from scratch.
In a clean, sterilised container, mix 200 g water and 200 g flour. You can use whichever kind of flour you like, whole-grains like wholemeal and spelt tend to speed things up, but you can use anything. Yeast bacteria lives on the flour – the water acts to kick-start the organisms into life, and then once they are awake, they feed off the sugars on the flour. Once you have mixed the flour and water together so that it is combined, cover the container and leave it in a warm place.
You are now going to give your starter its second feeding. Tip out a third of the flour and water mixture down the sink. Then, add in another 100 g of flour and a 100 g of water and mix well.
Day 3 to Day 5:
Repeat the steps from Day 2 , and give your starter a feed every day until Day 5.
Keep an eye on the way your yeast changes, it will start to bubble and the smell will change - from floury, to cheesy to alcoholy or fruity. Smells and bubbles all depend on many variables, so different flours, different temperatures of water and different temperatures in your kitchen will alter the results.
: Happy Birthday, your starter is a week old. Give it another feed as a birthday present - at this point it can start to be stored in the fridge.
Day 9, Day 11 & Day 13:
You will have started to notice changes and the fact you’re your yeast is growing in size with every feeding! Keep feeding it every other day and keep it in the fridge. After 2 weeks, you will have a lovely bubbly starter that is ready to bake with.
You can begin making bread! A good way of testing whether the sourdough starter is ready to bake with is by dropping a teaspoon of it into a glass of water. If it floats, it is ready! This is known as 'the float test.'
How to feed your yeast starter
(USE IF: you want to keep your starter active)
Feed your depleted sourdough starter water and flour, in equal parts, after you have made bread and between bread making sessions. The amount of water and flour needed depends on the amount that you have used for your last loaf and how much you need for your next loaf. At home, I usually use 200 g of water and 200 g flour for most feeds, unless I know that I will make a particularly large batch of dough next, in which case, I’ll add more.
Make sure that there is always enough sourdough to bake another loaf AND have some left over - never use all of the starter up when baking, or it will have to be made from scratch all over again.
How to revive your yeast starter
(USE IF: You've been given someone else's starter or you haven't fed your starter in a while, I'd say for over 2 weeks).
If the top of the starter is covered in a liquid or a crust, scrape this off the top and get rid of it. Add in 200 g flour and 200 g water and mix until fully combined. Cover and leave somewhere warm.
Days 3, 5, 7:
Tip out a third of your starter, add 100 g flour and 100 g water and mix well. After the seventh day, your starter will be bubbly and ready for bread-making again.
How much do I feed my starter?
When making bread, always work backwards. How much starter you will need to make depends on the amount you need for your next loaf. I personally to keep 200 g of starter on hand.
How often do I feed my starter?
The frequency of feeding depends on how often you bake bread. The rule that I generally go by is that, if I want to make bread on Wednesday, I will feed it on the Monday or Tuesday before and then once I have baked with it - therefore, if I bake once a week, I feed my starter twice a week.
But what if I don’t feed it?
Remember this – water wakes up the yeast that lives on the flour, the flour provides it with food. If you don’t add in water and flour, it will get pretty hungry, then go to sleep. (But it won’t necessarily die…) Furthermore, in this case, think of your sourdough as a hamster - discarding some of the starter and refeeding it is akin to clearing out a hamster’s cage and making sure it has fresh food.
Seriously though, I really don’t want to feed it.
Alright, that’s fine if you genuinely aren’t going to make bread for ages (I would also usually say if you are going to go on holiday use this tip, but looks like we’re stuck indoors for a while). If we go by the principle that water wakes up the yeast and flour feeds it, don’t add so much water into your mixture, so that it is less active. Therefore, rather than creating a mixture made from 50% flour and 50% water, make a mixture that is, for example, 70% flour and 30% water, stick it in the back of your fridge and forget about it for a while – the stiffer the starter mixture is, the less you need to feed it.
Is it dead yet?
Most likely, no. Yeasts are very, very tough cookies and you should pretty much never throw them away - they can almost always be revived! If you are thinking about throwing your yeast starter away, let’s go back to the hamster analogy - if your hamster wasn’t in the mood to play or was getting a bit sleepy, you wouldn’t throw it away, so why would you give up on your starter like that? If it does look a little worse for wear, try going back to the ‘How to revive your yeast starter’ bit and feed it up for a week or so until it is bubbling again.
How long can sourdough survive?
I once went to a birthday party for a sourdough starter that had been kept alive for 60 years - and if that isn’t old enough for you, I want to remind you about the games designer/ molecular physicist (commonly referred to as the world’s only gastroegyptologist)
who has managed to MAKE ACTUAL BREAD with the remnants of sourdough starter found in Ancient Egyptian pots. So, if you think your sourdough starter is dead after one week, think again. Sourdough starters are resilient little beasts and keeping one is a lesson in perseverance.
What should it smell like?
Welcome to the fragrant world of yeast strains. I recently had a complaint from a friend that their starter ‘smelling really, really rancid.’ Well, yes, most likely it does, because that is what fermentation entails and it absolutely does not smell delicious all the time. The smell of your starter will continue to change, but just remember that starter is a ferment, so it should smell similar to other fermented things like fruit, cheese, beer, wine, champagne etc. etc. There are clues in the smell - if it is really sour, like vinegar, then it needs a little fresh food. The best starter I ever made smelled consistently like miso paste and
swears that The Ultimate Starter should have the faint smell of bananas. Starter can also smell quite mild and floury at times - this is also fine, it just means it’s not as active. If it smells like damp or mould, however, don’t bake with it. I've also had (rare) reports of sourdough starters smelling like nailvarnish - this is one of the only times I will tell you to throw it away. If your starter smells like nailvarnish, I can only assume that this means it has started to create another type of alcohol - acetone - the type that you don't want to be ingesting, so I would start again!
Yuck, what’s that liquid?
Very often, you will end up with a thin layer of brown or grey liquid that sits on top of your starter. It looks terrifying but, essentially, it’s ethanol, or hooch - pure alcohol that the yeast excretes (kind of like yeast wee). But just because it's alcohol, doesn’t mean you should drink it - it won’t hurt you but it won’t taste good either, so instead, just scrape it off and throw it away.
Where should my starter live?
Temperature is important for the health of your starter - it should never be too hot or too cold. Some bakeries keep their starter in a cold store and others leave them at room temperature. I would, however, advise that if you are making bread less than twice a week, keep your starter in the ‘warmest’ part of your fridge (in the door, usually). Let it come to room temperature before baking with it and perhaps leave it somewhere comfortably warm just after feeding it. Whatever happens, you must make sure that the container that you keep your starter in is clean and sterilised.
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Troubleshooting: Sourdough Starters