No Acid Coffee
While it might be theoretically possible, it would not be practical or desirable for a coffee to have no acid. As a slow roaster, we reduce acidity levels between 70% and 85%. To achieve a 0% level of Chlorogenic acid in coffee, the coffee bean would have to be so thoroughly roasted, the coffee would not be worth drinking.
For most people the existence of a low amount of Chrolorganic acid is not the issue. The problem arises with the significant levels of Chlorogenic acid that is found in 99.98% of modern roast profiles. These modern profiles are too short in duration and they do not reach the temperatures to necessary to effectively reduce acid levels in coffee
So what is a safe level?. Certainly, people’s stomachs can have different sensitivity to the levels of acidity. Since there is no industry standard on what it means to be a low acid coffee, this can be a grey area. It also appears within the low acid community that there is no consensus of what constitutes low acid coffee either.
I suggest that any coffee that does not measures in the ph scale as 5.5 or higher is marginal at best. Also, looking at the coffee bean, I would need to see a reduction in Chlorogenic acid “dry basis” , which is the physical weight of the coffee by 70% or more from the original dry basis to the finished roast weight.