Beware of severe allergic reactions to pine nuts from China! My wife has made pesto with pine nuts for years, and I loved it and never had a problem. She would buy the large bags of Kirkland pine nuts from Costco. A large bag would last her a couple of years when stored in the refrigerator.
Then two years ago, she bought a new bag of Kirkland pine nuts from Costco and made pesto. I had an immediate reaction, my throat swelled partially shut and it was hard to breathe after one little bite. I took four Benadryl and a couple of hours later I was fine. I checked the package labeling on the pine nuts and found that it was from China. I was 60 at the time and have never had a nut allergy in my life. A few months later at a family dinner the same thing happened to me when pesto made with the same type of Costco pine nuts was served on noodles without my knowledge. I had a much greater reaction as I consumed a larger portion before I realized the problem, not only did it become hard to breathe but my face around my eyes swelled up as if I had been punched repeatedly. Six Benedryl and a day later I was OK.
Two days later I did a test. We also had a new purchase of Kirkland assorted nut packages in the house, the ones that come in a box of 24 with separated bags of peanuts, almonds, and cashews. We kept them for the kids, but I ate them on occasion. The peanut bags were labeled "processed in China", the others...almonds and cashews were not from China. I ate five peanuts and waited. Within 10 minutes I had a reaction. Two Benadryl and one hour later I was fine.
It is now two years later. I still eat pine nuts, peanuts and every other kind of nut without a single reaction; but I check the label at the store before I purchase. If it is processed in China, I do not buy it. So please be aware, I do not believe that it is the nuts that are the problem. Instead I believe it is something in the processing of the nuts in China that I am allergic too.