The starter looks disappointingly calm; the foaming and bubbling seems to have subsided, and I’m wondering: is it possible that it’s died? All the material I’ve read so far says that making a sourdough starter is just about idiot-proof. It still smells lightly sour and fruity, and there are a few small bubbles, but nothing as energetic looking as Day 2. I decide that it’s time to do a bit more research. In the meantime, I feed it again (throw out 1 cup of the mixture, and feed it half a cup of flour and half a cup of water.) A few more bubbles appear as I stir it up – encouraging. Doesn’t look dead.
A bit more internet searching sets me straight on several of the myths and facts around sourdough, and turns up some interesting and informative links.
Myths about sourdough
1. Wild yeasts come from the air. Not true: although some wild yeasts may indeed live in the air around us, your sourdough is most likely to develop from the yeasts on the flour itself (or on the grapes or other fruit, if you use those to make your starter).
2. Metal spoons reacts badly with the sourdough starter. Well, sourdough is acidic, and may dissolve some metals if you expose them to each other for long enough. But a stainless steel measuring cup or spoon is very unlikely to interfere with the composition of your starter.
3. You have to use special water (bottled or spring water) for your starter. Not true either. If your tap water tastes and smells ok to drink, it’s probably fine for starting a sourdough.
These and other myths are explained in good, clear detail on Mike Avery’s fabulous, informative site. I really enjoyed Mike’s explanations, and he also gives three different approaches to making sourdough. Mike would classify me as one of the worst beginner sourdough makers – one of those that insists on making their own starter. Sounds like he gets more emails and complaints and questions from beginners who’ve confused and frustrated themselves with exactly the kind of of DIY approach to sourdough that I’m so happily embracing! Anyway, even though I’m breaking all Mike’s rules, I did get lots of good advice and encouragement from his page on starting a starter.
I discovered the possible cause of the exciting Day 2 activity (and why it subsided so quickly): a bacteria called leuconostoc which is found in many strains of flour. When this bacteria multiplies, it produces lots of carbon dioxide, and makes your starter look like it’s very active. But after another day or so, the leuconostoc kills itself off (if the yeast is growing happily), and it suddenly looks like the whole mixture is going dormant. This alarms many sourdough newbies, who panic and throw away their starter prematurely.
So, that was reassuring. Gave the mixture another feed and a stir in the evening, using Mike’s ratio of 5/8 cup flour to 3/8 cup water (after throwing out a cup of the starter, in order to keep the volume stable). Fermentation, it seems, is not an instant sort of thing!