I've eaten pine nuts all my life and never had a problem till this past year. In the past 10 months I've had pine nuts from Sun Ridge Farms that are supposedly from Santa Cruz and experienced bad reactions with two different bags. But other times I’ve used Sun Ridge Farms and had no reaction. The bag states they are manufactured in Santa Cruz, but the package copy reads: “Our buyers travel extensively throughout the world to visit farms and ensure we pack only the freshest, most delicious and highest quality nuts and seeds available.” Well then that might explain the inconsistency in the packages. It seems that Sun Ridge Farms does not grow pine nuts, they just source them. Perhaps some of those “high quality" nuts came from China?
The same thing has occurred with pine nuts bought in bulk from Whole Foods. Sometimes they were fine and sometimes not.
How I used them did not seem to matter. I once made pesto and experienced a 12-day period of metallic taste and slight tingling burning sensation on my tongue. I also had a bad experience when I lightly toasted the nuts and tossed them over roasted broccoli.
It is only after I searched for the causes and symptoms of severe “metallic taste” that I came across the “pine mouth” posts (see more links below) that described my experience exactly. In addition to the bad taste, I noticed a slight swollen feeling and pale coating on my tongue.
In my case, the symptoms came on the day after and sometimes two days after eating pine nuts. In all instances the symptoms went away after 5 to 15 days, with my ability to taste as normal, increasing gradually each day.
The first time this happened it was very disturbing and I kept thinking it was due to tainted almonds or cheerios since that was what I ate when I first noticed the horrible taste. Subsequently, I was able to trace the common denominator of pine nuts in each occurrence.
If you are not sure if this ever happened to you, I can assure you it hasn’t-- because if it did, you would definitely know. It is not a mild annoyance by any means. It’s quite horrible. In fact, if this sensation could be purposefully induced, it would become the worlds best diet aid ever because you really can’t eat it’s so awful. It makes you avoid all food. Drinking wine while this is happening is impossible. It tastes like poison. Scary stuff.
So my big reason for writing this is to warn others. As much as I love pesto and using pine nuts in recipes, I have decided to delete them from my diet forever. I will make an exception when I am in Italy and the pine nuts are local. But otherwise it’s just too risky and who knows what the cause really is? We know so little about our food and where it really comes from. Unless we grow it ourselves, it’s impossible to know. We all know what happened with the pet food from China. I’m not going to gamble with Chinese pine nuts.
My advice to wineries…I would absolutely avoid the use of pine nuts in any recipes you serve for food pairings and forbid your caterers to use them at your events. It would be very easy for someone to mistakenly believe your wine is horrid, when what they are really experiencing is a reaction to pine nuts. None of my pine nut reactions have been instant, it’s always been a day or two later, but why take the risk?
Links for Further Reading:
EXCERPT From Wikpedia-- Risks of eating pine nuts:
A small minority of pine nuts can cause taste disturbances, developing 1–3 days after consumption and lasting for days or weeks. A bitter, metallic taste is described. Though very unpleasant, there are no lasting effects. This phenomenon was first described in a scientific paper in 2001. Some publications have made reference to this phenomenon as "pine mouth". This is a relatively new phenomenon and appears to be most common in nuts coming from China. It has been theorized that the nut trees are absorbing something and passing it on to the nuts, or the nuts themselves are being treated with something before packaging. It is also possible that the nuts have spoiled and are rancid, causing the metallic taste disturbance. Also, it has been hypothesized that this bitter side effect is caused by an allergy that some people may have to pine nuts, but this does not explain the recent appearance of this syndrome. Metallic taste disturbance known as metallogeusia, are reported 1–3 days after ingestion, being worse on day 2 and lasting for up to 2 weeks. Cases were self-limited and resolve without treatment.