I was doing a little research on fermentation (primarily of grains) and came across a really useful on-line booklet entitled, Fermented Cereals. A Global Perspective. Oddly enough, they also have Fermented Frutis and Vegetables. A Global Perspective (and yes, it was misspelled on the site).
The Cereals book has a good overview of the health reasons for fermenting grains, but it also has a good survey of different indigenous fermentation practices from different parts of the world. It’s probably not adequate for instructional purposes, but is a good place to start.
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