How to Keep Your Sourdough Starter Happy in Summer

I'm fairly certain I've mentioned it before - my sourdough loves summer. The starter activates quickly, and the loaves are more easily over-proved (something that sadly usually happens to my first few loaves coming out of winter - I tend to forget they'll rise quickly and leave them for the same length of time I do in winter!).

Like most living things, my sourdough starter requires slightly different care during the warmer months, so I thought today I'd share with you how I keep her happy during summer. I'll also be touching briefly on how your sourdough starter actually works, hopefully so that you understand her needs better and know how to adjust her care accordingly.

Let's talk sourdough starters, shall we?

Just like my starter, you've probably noticed that your's activates more quickly at the moment too.
You might have also noticed that it bubbles to life and then goes flat a few hours later.

Sourdough starter works by the natural yeast found in the flour feeding on the carbohydrates, producing carbon dioxide and ethanol in the process. The carbon dioxide is visible as the bubbles in your sourdough starter, and it's what makes the bread rise.

The warmer the weather, the faster the yeast "eats", producing lots of carbon dioxide or bubbles. This is why sourdough starter is faster to activate in summer and why you'll notice your loaves rise much more quickly.
You know how your bread springs when it goes into the oven? That's the heat causing the yeast to go on a feeding frenzy. The high temperature then kills them, so don't put your sourdough starter into the oven!

In cool temperatures however, such as winter or when you put your starter into the fridge, this process is much, much slower. That's why putting your starter into the fridge stops you having to feed it every day. It's still alive, still working, it's just doing it at a snail's pace.

(Below is pictured my sourdough starter still bubbling, albeit slowly, in the fridge)

So why does your starter go flat in summer after being bubbly only a few hours ago?
In very basic terms, the yeast virtually runs out of food. It's fed on the carbohydrates, producing lots of bubbles in the process, and then run out. It's got nothing left to feed on. This is why we feed or refresh the starter by giving it more flour and water.
The fresh flour is like new food for your starter.

If you wanted to make a loaf from your starter, and it was active a few hours before but is now flat, use it anyway. The flour in your loaf will give the starter something to "eat", and your loaf will still rise.

To keep my starter happy in really hot weather, I have two different strategies.

One option is to feed it less, more often. Rather than refreshing it in the morning and evening with 100 grams each of flour and water, I feed it morning, lunchtime and evening with 50 grams each of flour and water. It's getting an extra 50gms of flour across the day.

However, this option only tends to work well when my starter is quite small, after a big bake when I'm in the process of building her back up again.

When my starter is larger, or I don't want to have to remember to give her an extra feed, I still only refresh her twice a day. For each feed, however, I increase the amount of flour I'm adding from 100g up to 250g, with equal parts of water of course.
This is a really fast way to get my starter up to a large size again quickly, and in hot weather adding that much flour at once makes her really happy.

I hope this has helped you understand your sourdough starter better, and that you'll be able to keep her bubbling away over summer.

Perhaps you might have some sourdough starter care tips of your own?
Share below and let me know your thoughts on today's post too!

Happy sourdough baking x

If you enjoyed this post, you may also enjoy my eBook, Spelt Sourdough Made Simple.

Designed for baking with whole spelt flour (and other variations of spelt) with no mixing in of other flours - this is truly 100% spelt sourdough. Also suitable for whole wheat flour baking.
Learn more or purchase your instant download copy here.




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