TLDW: Their mandarin orange wine was a bit too bitter. Testing, unscientifically, if they can tell a difference. They can. They think it lowers the bitterness.
Interesting. I’m mainly a beer brewer (only my first cider recently) so I’ve not had a brew that’s “too bitter”, as with beer you WANT them to be bitter, usually. I’ve heard to add a pinch of salt to a pot of coffee.
I would probably not do that because I’d be worried that it’ll destroy the whole batch.