I’ve assumed a bit of prior knowledge to sourdough baking in this blog post. I’m happy to answer any questions where things aren’t clear because of that, though I might just point you off to other more baking-focused sites to read up on stuff.
During the Christmas break, I decided to start baking sourdough bread again. My problem was that my sourdough starter, Queenie, who I’d been keeping in the fridge, had gone off. I’d killed her through neglect.
Fortunately, a while ago, I had the foresight to freeze some samples of Queen when she was at her most active. Rather than start with making a new sourdough starter from scratch – which is admittedly not that difficult but can take up to a week – I decided to see if the cryogenics had worked.
Here’s the bag containing those starters I divided up into 50g discs nearly three years ago. Why discs? Well, I think my theory was – still is – that flattened discs will thaw out more quickly than a ball. I took just one of these discs and let it thaw out for a day before feeding it a standard 50/50 water and flour mix (I think I started with 25g of each).
To be honest, my hopes weren’t high after the first couple of days. Queenie was a bit sleepy and there were only a few bubbles in the sourdough starter mixture. I probably could have achieved the same level of activity by just starting from new. Looking back now, I think the discs weren’t a 50/50 mix so could probably have done with some more water to start with.
It was a good four days before I got some proper signs of life but once Queenie woke up, she really woke up. She was bubbling so furiously, she was spilling out of the jar and I had to transfer her into a large Tupperware container. But my objective was achieved and I had a usable, active starter again and one that I could smugly proclaim was several years old. (I won’t go into why a sourdough starter can’t really claim to be that old. Not today, anyway.)
So there you have it: freezing a sourdough starter for long-term storage and subsequent revival is a viable option.
These are the options as I see them for storing an active, lively sourdough starter.
- A 50/50 mix is fine if you’re going to bake sourdough regularly and have the time and organisational skills to feed it every day. Probably overkill for those of us who don’t bake three or more loaves a week.
- A newly-fed 50/50 mix will keep in the fridge for at least a week, sometimes up to a month, without feeding but do keep an eye on it. You’ll also need to remember to take it out of the fridge in time to bring it up to temperature to start using it in a recipe.
- Credit to Dan Lepard for this particular tip. A 65/35 flour to water or even 70/30 mix will keep longer than the standard 50/50 mix. Instead of a gloopy batter, you have more of a malleable dough. For the occasional sourdough baker, it’s a good way of keeping a starter without having to worry too much about tending to it. Obviously don’t leave it for a year or something stupid.When it comes to using it to make a loaf, you need to adjust your recipe to compensate for the fact there’s more flour than water in your starter. You might even want to mix it with a bit of water to bring the balance back up to 50/50 and leaving it for a while before mixing it in with the rest of your ingredients. (Kind of equivalent to activating commercial yeast in warm water first, I guess.)
- Credit to Dan Lepard for this tip, too. For the lowest maintenance, freeze your starter. I don’t think it particularly matters if you freeze a 5050 mix or a stiffer one like I’ve just mentioned, though the 50/50 mix makes it easier on the maths because you just need to add your frozen disc to a similar 50/50 mix. Then just keep working with it like you would a normal starter, feeding it a 50/50 flour/water mix each day until you breed a monster clone like I did. I wouldn’t advocate using a frozen starter direct in a recipe. The way I see it, you’re using it as a shortcut to a fresh starter and saving yourself several days of cultivating new yeast.
I stumbled – well, ambled towards, really – a method of making a sourdough loaf that puts an end to the ‘how sleepy or awake will the starter yeast be today’ guessing game but I’ll save that for another post.