Learning about sourdough

September is for sourdough

Every September since 2013, the Real Bread Campaign has had a month long Sourdough September event to promote sourdough. At the Heron Corn Mill, we will be celebrating our second Sourdough September with an all-day sourdough adventure in the shepherd's hut.

Sourdough is definitely not for the faint-hearted, and the idea of guiding a group of bakers through the minefield that is sourdough sends me weak at the knees. So between now and September I will be monitoring my sourdough starter culture and making sure it is in really tip top condition by the time baking day arrives.

Like last year I will be creating a brand new culture in my sourdough laboratory at home, using Heron rye flour, so that we can see the difference between a wheat culture and a rye culture.

Baking with rye is particularly challenging, and baking rye sourdough is if anything even more so. Making a rye starter last year taught me quite a few lessons along the way, not least about keeping on top of hydration.

It was a big mistake to allow the consistency of my culture to vary over time as I fed it, and try to calculate the ever-changing ratio of water to flour. With hindsight rather than just recording what I added, I should have kept everything in the same ratio by very carefully weighing 7 parts water to 5 parts flour every time I fed.

This year I have ordered a camcorder so I can keep a video diary of how the cultures develop up to baking day. Hopefully this will help me to see clearly where I got things right, and where I didn't.

Learning about sourdough by doing nothing

Sourdough never sleeps - it just dozes off. But even when it appears to be dormant, the character is slowly changing, and not always for the better. A sourdough culture can be a bit of a beast.

Fortunately though, my culture has been very predictable and reliable.  I've had along run of baking sourdough every week and the culture has settled into a good routine.

But this summer I have discovered the joys of yeasted white bread baked without a tin or a basket, just straight onto a tray. And as there is only so much bread you can eat, sourdough has rather taken a back seat. I've fed my culure a couple of times, and otherwise just let it rest in the fridge.

When I finally did come to bake some sourdough again, I got the culture out a couple of days before baking, and fed it again. Then I made a sponge the day before baking, as I usually do. On baking day I was a bit surprised to find that the sponge wasn't as vigorous as I was used to finding it. And when the bread came out, I found that it was considerably sourer than usual.

Some people really like their sourdough tangy, which is fine. The ultimate really sour sourdough is the San Francisco version, which is very challenging stuff indeed. My own preference is for as little actual sourness as possible. What I like is bread with as much sponginess and body as possible, and just a touch of "attitude" in the flavour. My sourdough this time was several notches closer to San Francisco than normal.

Clearly, there was something to learn here. I'd fed the culture, I'd made a sponge, but the result was quite different. So what had I done differently? Well, I hadn't baked off it or made a sponge with it for a long time.

Most bakers tend to feed their culture in the pot, and then take some out to bake with. I don't like this at all, because the part that stays in the pot can just get older and  older. Much better, I think, is to take the whole of the culture out of the pot to make a sponge with, and then take some of the sponge back to keep for next time. My recent experience with this sourer-than-usual sourdough just shows why my sponge method is so good.

When you make a sponge, the 80 g or so of culture is bulked up to about 680 g of sponge, and then 80 g of sponge is taken back for next time. So very very little of the 80 g of culture in my pot this week was there last week. And it's had a really good feed on many times its own weight in fresh water and fresh flour. Sponging is like a complete makeover for a starter, whereas feeding in the pot is more like life support.

Moral of the story

If you just feed your starter, then at the very least make sure you throw most of it away beforehand. And if at all possible, sponge and bake from your culture rather than just feeding it.