I know some of you don't like to read lengthy stories, so I'll try to be succinct. I read Cook's Illustrated cover to cover. In the latest issue, under Notes From Readers, someone writes in about having a strange taste in their mouth after eating pesto. The problem lasted for days. There are pine nuts in pesto.
It has been discovered that China has introduced two species of pine nut that have
never been used for human consumption. The condition is called "Pine Mouth". It makes everything you eat and drink taste bitter and/or metallic. It can last as long as two weeks. No lasting effects,
so far.
Moral of the story. Don't buy cheap chinese shit. Only buy European or Middle-Eastern grown pine nuts. They may cost more, but you won't end up with Pine Mouth.
I try very hard NOT to buy chinese crap. Sometimes it is tough to do, but I'd like to live a nice long life and it seems that they don't want us to.