BITTER METALLIC TASTE AFTER EATING

I experienced a bitter metallic taste after everything I ate (out of the blue). Thought it might be GERD (not on any medication). I figured it out. I ate PINE NUTS 2 days ago. There are thousands of people who experienced this. Cannot be placebo as I have eaten them before and never had this issue. Everyone experiences the exact same thing:

Horrible bitter taste in mouth (while eating) and throat 1-3 days AFTER ingesting pine nuts. Not an allergic reaction. Unknown chemical in a specific species. This lasts 10 -21 days in ALL cases.

Any Idea what might cause this. Google "pine nut bitter taste"