Wednesday, 8 April 2015

Project Sourdough: Care and Feeding

First things first, I've got to apologise for the photo quality here. A sourdough starter is not a photogenic creature. But it's a creature! Nearly a week old, my little colony is alive and well. I've found an excellent resource in this website, Sourdough Home, so I've been taking my advice from there among other places.

So, how do I know that we've got a live yeast culture?
The air bubbles in the photo below are a dead giveaway. The air is the waste product of our friendly 'critters' - yeast and lactobacillus bacteria. The starter also doubled in size. I let it sit at room temperature for three days, then I fed it and have been storing in the fridge ever since, to slow down the process for a novice like myself. 
How do we know when to feed it?
Our friendly 'critters' (it seems that sourdough nerds favour this word, and I'm going to use it too, rather than say 'yeast and lactobacillus bateria' every time) can only make the dough rise so much before it begins to fall as their food source declines, and they need to be fed again. Can you see the cracks in top below? That shows that it has risen as much as possible, and had begun falling. It will roughly double in size, then begin to fall. If you wait too long to feed, you can have problems with your starter, and that boozy liquid I mentioned last time is actually a sign that you've waited too long (and it's called 'hooch', btw). You can feed as often as every 12 hours, or as little as every few days at this stage. One reason I am storing mine in the fridge is to reduce the frequency of feeding while I get to know this process a bit better.
How do I know we've got the right critters?
This was fascinating to me - apparently there are many strains of yeast and bacteria that can successfully raise bread, and the organic rye flour we started with would have given us many, many microorganisms to cultivate, not all of them good. But if we keep the right conditions, our good critters will thrive while the bad critters die out. At the first feeding, I have to admit that the starter did not smell good. It had an 'off' smell, and you wouldn't dare eat it or bake with it. Since feeding, the aroma has improved dramatically, and now it smells complex, but not BAD. Sourdough Home recommends never using a starter that is less than a week old (or unable to double in size between feedings), and I can see why - you don't want to use it until your good critters really own the place. I plan on waiting probably another week before attempting a loaf, and even then I am going to let my nose guide me a bit.
What do you feed it?
Now, I mentioned that our rye flour gave us a wealth of microorganisms to start with - this is a good thing when you are starting from scratch, but is it a good thing to be continually reintroducing new critters into the mix when you feed? There doesn't seem to be a consensus on this question, but some experts recommend switching to plain flour for feeds, and it's also a cheaper option. However, plain flour is high in gluten, potentially making it a little trickier to work with. I plan on using both, and just seeing how we go. Feeding plain for now, but if it gets a bit too gluten-y, I'll use rye again.
How do you feed it?
You just discard (at this stage) up to half your starter, and add equal weights (not volumes!) flour and water. Simple. Within minutes, we had new air bubbles forming.
And that's all I've learned about sourdough this week! Wish us luck!


  1. Don't know if it applies to sourdough but I like the term "Scoby" (symbiotic culture of bacteria and yeast) they use in kombucha brewing. I just think it's cute.

    1. I like it! Do you brew your own kombucha?!