This is an interesting discussion. Here's another short article
https://navitasorganics.zendesk.com/hc/en-us/articles/360052769251-Are-Elderberries-toxic- with this intriguing comment:
Hm... does fermentation destroy cyanogenic glycosides? I couldn't find a study on wine or mead, but I did find one on lacto-fermentation of flax seed. It turns out that flax seeds also contain cyanogenic glycosides. They found that after 48 hours of fermentation, 99.3% of the cyanogenic glycosides had been destroyed:
An efficient fermentation method for the degradation of cyanogenic glycosides in flaxseed - PubMed
Interesting... but there are some caveats:
* this study was on lacto-fermentaion, not wine yeast
* they used flax seed, not elderberries
* the study was done under "optimised conditions"
OTOH, here is an anectdotal report of someone getting sick from eating 1/4 cup of dried elderberries:
The Side Effects of Eating Elderberries Raw, A Personal Experience This is a personal experience, not a scientific study. Maybe the author is especially sensitive to cyanogenic glycosides. But I want to look at both sides of this issue.
Many websites say that it is dangerous to eat raw elderberries and that they must be cooked But they are mostly quoting each other, so it has become one of those "everyone knows this" kind of things. I will continue to look for actual scientific studies on this topic. I want to see actual evidence.
Each of us needs to evaluate the evidence and make our own decision depending on our risk tolerance. I don't claim to be an expert on any of this.
@Dan O I don't know whether elderberries have pectic. My completely uneducated guess would be that they do not, or do not have much. But I usually add a dose of pectic enzyme to all my fruit wines/mead to be on the safe side.