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ereyes01 · 2019-06-25 · Original thread
I really enjoyed Home Coffee Roasting by Kenneth Davids: https://www.amazon.com/Home-Coffee-Roasting-Revised-Updated/...

It's not about grinders but it spends a few chapters on how coffee is produced and how different factors/regions can affect its flavor. It's an excellent primer on coffee in general, and of course on roasting at home (though the chapter on machines at the end is a little outdated).