It was pointed out that I came out a little forcefully against fruit-based sourdough starters the other day. It was further pointed out that they’re a perfectly sound way of getting a yeast-bacteria tag team culture going. To that I have to say that I’ve never had success with that particular method, possibly because the fruits I’ve used have had pesticide residues on them, but probably because the bugs on the fruits just couldn’t hack it here in the take-no-prisoners wilds of Lousiville.
But let’s be clear on this: there are all kinds of ways to get sourdough yeast-bacteria cultures going. Some people like to use fruit. Some people like to use plain white flour and water (one of those people is me). Others like to use rye flour and water, since rye flour is a veritable zoo of microbes, and chock-a-block with enzymes and sugars. Still others like to buy sourdough starters from mail order houses since the culture is a known commodity.
What all these methods have in common is that sooner or later they all turn into cultures of locally-based micro-flora and/or fauna. Me, I like to take the direct route and invite the locals in right off the bat. It’s far easier than trying to keep bugs from other parts of the world alive, since many of them are so sensitive even small changes in temperature, humidity or water chemistry will kill them. From a microbial perspective, the world is divided up into hundreds of thousands (maybe millions) of micro-climates, each of which can have microbes so perfectly adapted to live in them that a displacement of even a few miles can be lethal. Which means eventually just about any starter critter you bring into your home will be out-competed by the ones adapted to your local air and water. It may take days, it may take weeks, but sooner or later the interlopers will be driven out.