Keep an eye on the weather when baking

This weekend at Heron Corn Mill we had another boon day, when volunteers of all ages come and do a bit of general tidying up around the mill. In return they get a fun day in the sun in each other's good company, and the mill provides a lunch to say "thank you for your hard work". This time it was me doing the lunch.

As part of the meal, I thought I'd offer a choice of breads - some using the excellent Heron Corn Mill flour and commercial yeast, and some white sourdough.

Crank up the starter...

Making sourdough needs some preparation a couple of days in advance. You make a "quarter sponge" by gradually bulking up your starter until you have fed it a quarter of your bread flour. Then you leave it overnight. The wild yeast in the sponge breaks down the starch in the flour into sugars and various good acids. Getting the sourness right is a matter of timing and managing the yeast. It's like a fitness regime, aiming for peak condition at race time, only in this case it's aiming for peak condition at baking time.

Somewhere along the line I lost the plot and before I knew it I had enough starter to feed the five thousand. What to do?

Loafing around

I've been doing some experiments recently with "pain de campagne" - country bread that starts off with a sponge and then has commercial yeast added to the dough on baking day. So I thought I might as well use up my spare starter in some country bread. What could possibly go wrong?

Bread is reasonably predictable. If you use the same amount of yeast and let the dough rise for the same amount of time, you will get similar bread at the end. But if you start to vary the yeast or the timing, your bread will be different.

And another thing...

There is one more thing that affects your bread - the weather. The week before the boon day was just one warm day after another. As one baker from Bread of Heron, the Heron Corn Mill's bread group, said -

For once the instructions ‘leave for an hour to double in size’ is correct.

When you make sourdough it's vital that you observe what is happening and react accordingly. You have to fit everything else in around your sourdough. But what did I do?

Winging it...

I was at the mill the afternoon before baking day, preparing the boon day lunch. So I made up the dough alongside everything else and left it to rise in the bowl overnight. I never even thought about the warm weather. Normally the yeast feeds on a quarter of the bread flour for about 8 to 10 hours in a cool room. This time it fed on all the flour for about 16 hours in a warm room. What was I thinking of? Of course the bread was sourer than usual! 

The debrief...

I'd broken my own golden rule. Instead of noticing the warm weather and managing the wild yeast accordingly, I let it loose with more food, more time, more warmth.

Bread is very much a matter of taste, and my boon day bread may have been just right for some people. But I like my sourdough milder. Still, it wasn't the end of the world.

There's always next time...

A real baker would just have made the quarter sponge as usual and got up really early on baking day to make the dough. But that requires a whole extra level of commitment. You have to suffer for your art.

For a home baker like me, it's just one more lesson to learn: observe the weather conditions and react accordingly.