aandrew4

...and from different parts of the world.

...or indeed with different batches of grain.

I would also like to see if/how the microbiome changes as the source grain(s) age. We do kettle sours with starter cultures set up with Weyermanns acidulated malt and local grain from a local maltster to give us a local character. I have noticed that what I see under the microscope changes, for instance the most recent batch showed very little by way of wild yeast. It may just be initial starting conditions, or temperature, or some other factor or combination of factors, but I do wonder if it is mostly driven by what is on the grain and that that may change over time.