On the Coffee Research dot org site a well referenced discussion of coffee acidity
( http://www.coffeeresearch.org/science/sourmain.htm )
Note the discussion in the body of the text “Excessive quinic acid has been associated with unfavorable sourness when coffees are roasted too dark or brewed coffee is left on a heater plate. This sourness, however, is contradictory to the rise in pH and reduced perceived acidity at darker roasts and is likely operating under a different mechanism“.
Our roast degree series near the end of the foam stability observations.
OSU
After experimenting roasting my own coffee, I learned that darker roasting drastically reduces the acidity regardless of brand. That said, some beans do have more acid, but roasting seems to be the most effective way to control acid.
Regards,
Rob
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