[kthxb]

Well, you do bootstrap your sourdough bread when using sourdough starter from previous batches...

[andrey_utkin]

That seems like just one extra steps in your technology, but not a hermetic bootstrapping.

How do you get your first batch started? Must be you rely on the fact that

> Flour naturally contains a variety of yeasts and bacteria

https://en.wikipedia.org/wiki/Sourdough#Starter

So you either take your starter from somebody else or you fall back to a lower-level prerequisite of dormant living organisms present in your flour, and you hope they are alive and good for your end product.

It's not that hard to imagine that these bacteria are killed by irradiation, or are "compromised by perfectly placed state-level adversary".

[galangalalgol]

Much of the yeast and bacteria come from the air. That is why it tastes different in different cities.

[wiredfool]

It's mostly from the flour, because the yeast has evolved to eat the wheat. It's most likely to be found where there's food, not in the air.

[IIAOPSW]

I think you missed the point. There is no first batch. It's sourdough all the way down.