A few years ago, I had a particularly bountiful crop of basil in my garden. Autumn had come and we were due for a freeze, so I went ahead and picked all of it and decided to make pesto and freeze it for delicious pasta dishes throughout the winter. Have you ever made pesto? It’s super easy – you just throw some olive oil, basil, pine nuts and Parmesan cheese into a food processor, hit the button a few times, and that’s all there is to it. Of course, I had to have some that night, mixed in with some linguine and accompanied by some toasty garlic bread – and it was fabulous (if I say so myself).

So delicious – so easy – SO DANGEROUS!
A night or two later, I woke with a horrible taste in my mouth – and when I say “I woke” – I mean that literally. The bitter, metallic taste woke me up in the middle of the night! I brushed my teeth, but the toothpaste also tasted disgusting. In fact, everything I ate tasted awful! You’d think that would be a great diet – we’ll call it the “metal mouth” diet – but actually it was just the opposite. The taste was so nasty that I kept eating all sorts of food, trying to get that taste out of my mouth and find something I could eat and enjoy. Nothing worked and after a few days, I started to worry that I had a brain tumor or something equally serious wrong with me.
So, I did what any person who is in fear for their life but hates going to the doctor would do – I Googled my symptoms. And this time, instead of being told I had cancer, the diagnosis was pretty straightforward – I had Pine Mouth. This affliction comes from eating certain kinds of pine nuts – usually those imported from China. I quickly checked my package of pine nuts, purchased from Trader Joes and, sure enough, they were from China. (Disclaimer: this was 2-3 years ago. I don’t know if Trader Joes still sells pine nuts from China)
No one knows exactly why people get Pine Mouth or why it affects some people over others. There was no real treatment, but I was assured that it would disappear in time – usually two weeks to two months. Two months! I couldn’t imagine going that long with that crappy taste in my mouth. As it turns out, I didn’t have to wait that long – but it was two or three weeks of….ugh.
I know I could make my pesto with walnuts as a substitute instead, but I love the taste and texture of pine nuts – in pesto, on salads, and just to snack on, so I didn’t want to give them up. But, as you can imagine, since then I’ve been very careful when I buy pine nuts. I make sure they are a US product, or at least not from China. I also learned that you can tell by the size and shape of the pine nut whether they are going to be potentially problematic – but I didn’t learn that until last week, when it was too late.
Fast forward to a week ago. A dear friend of mine gave me a gift box from one of those places that deliver everything to make your meals for the week. It was super fun! Every meal was packaged with all of the ingredients, including tiny packets and bottles of spices, condiments, vinegar, and the like. My son, who usually spends his at home hours holed up in his office on the computer, only to be seen in glimpses as he ventures out to grab a soda, actually joined me in the kitchen to help me cook and then we ate our dinners at the table! Like grown up people!!
One of the first meals I made was a mushroom-artichoke risotto, garnished with parsley and pine nuts. I blame myself – I didn’t even think twice about the pine nuts. I just sprinkled those suckers on my risotto and dove right in – and it was nummy! Sure enough, the next night that nasty taste woke me up in the night. I didn’t even have to Google it this time – I knew what it was – the dreaded Pine Mouth.
What was heartbreaking about this round of Pine Mouth was that I still had two meals left to prepare from my box of deliciousness. This is all fresh food and produce, so it wasn’t like I could just put off making them for two weeks while I waited for the symptoms to dissipate! I was determined to fight back!
That day at work, I fired up my computer and started looking for a treatment. It had been two or three years since my last bout with Pine Mouth – surely there had been some scientific discoveries in the meantime! It took me several hours – don’t tell my boss – but I found some interesting and helpful information. I thought I would share it here – just in case you are ever plagued by Pine Mouth. You’re welcome.
First of all, Pine Mouth is not from an allergy to pine nuts, per the US Food and Drug Administration. In response to complaints since 2010, they analyzed samples of pine nuts and found that, in the majority of cases, the pine nuts were consumed raw and did not taste rancid or “off”. There was also a chemical analysis run by Swiss researchers and they found two varieties of pine nuts that had different fatty acid profiles from other pine nuts – so they think that might be a factor. Both of these pine nuts were Chinese.
A graduate student named Grace did her thesis on Pine Mouth Syndrome and she found that one variety of Chinese pine nuts, called P. armandii, were the common denominator in all of the cases that she studied. They have a distinctive shape when compared to other imported pine nuts. Had I known and had I looked more closely, I could have identified that the pine nuts I had been sent with my food box were a possible culprit.

Avoid the P.armandii pine nuts at all costs!
My best discovery – and it wasn’t really my discovery – I just happened to find the website of the discoverer – was a treatment for the dreaded Pine Mouth Syndrome! Dr. Kevin Wang, PhD had a bout of Pine Mouth himself, and theorized that the nasty taste was the result of the fatty acids from the affected pine nuts being deposited on the plaque of the tongue — particularly near the back, since there is more plaque there. The fatty acids then activate the taste bud receptors to be overly sensitive to the bitter tasting chemicals. Since plaque is somewhat difficult to remove, he suggested using a spoon, fingernail, or toothbrush to remove the plaque.
Everybody has plaque on their tongue – pull out a mirror and take a look. It’s that white colored coating you see. If you scrap at it with a spoon, it actually collects on the spoon and you can see the plaque mixed in with your saliva. Dr. Wang advises to remove the plaque a bit at a time and rinse out your mouth with warm water – repeating until most of the plaque is gone. I immediately grabbed a plastic spoon I had handy and went to work. It seemed that it was working and the bitter taste was not as pronounced.
Dr. Wang also found that eating fresh pineapple can be helpful. Pineapple has an enzyme in that basically eats the protein receptors on the taste-buds where the pine nut chemical is stuck. He suggests that you chew a couple of pineapple pieces at a time for about 60 seconds. You can then either swallow or spit them out. Repeat that 5 or 6 times per session and you can repeat sessions once or twice a day.
During my lunch hour, I visited a nearby grocery store and picked up a tongue scraper (which has the added benefit of helping to reduce bad breath) and a container of freshly cut pineapple. I spent the remainder of my day (yes, it wasn’t a particularly productive work day due to my obsession – but I had a pine mouth emergency, dammit!) alternatively scraping my tongue, swishing water, and eating pineapple.
And it worked!
By that night, the bitter taste had significantly decreased. I was able to eat and drink and actually enjoy the taste! By the next day, I could barely detect the metallic taste in my mouth at all!
Now, I do have to add some caveats, based on my personal experience. Be careful not to go too wild with the tongue scraping, especially if you are also going to be eating pineapple. It could bring about an annoying canker sore and you don’t want to exchange one problem for another. It’s also best to do the tongue scraping in the privacy of your bathroom – having someone walk into your office when you have an implement so far down your throat that you are practically gagging is difficult to explain. And finally, stick to American pine nuts (or at least avoid any from China) and you probably will never have to deal with this issue at all!
Happy pesto-ing!
Okay. Pine mouth. Check. That is bizarre. I love pine nuts, so I am glad I don’t get that. I also am certain we were separated at birth. haha.
I love them too! I’m not giving them up — I’m just going to be more selective in where they are grown. Here in New Mexico, we have lots of Pinon trees (upon which pine nuts grow) and people are always selling them by the side of the road. Maybe I just need to find a grove of Pinon trees and harvest my own (although there is a danger of getting hantavirus from the rodent droppings around the trees — so maybe not). And yes — we were separated at birth! One of these days I’m going to show up on your doorstep and meet you in person (and of course, you are always welcome at my place).
YIKES! I never ever knew that was a thing! I don’t think I’ve really had much exposure to pine nuts, but I LOVE pesto (as long as it has no parmesan in it) and what a shame your batch was a waste 🙁
Pesto is the best! I wish it didn’t have so much olive oil in it – but I just keep telling myself its a good fat!
It’s better than a lot of the others 🙂
Been there, had that. It’s awful. Haven’t touched a pine nut since. But I might try it, now that I know what to look for. Thanks for passing along the info!
When I had it, the tongue scraping method hadn’t been discovered yet. I accidentally found a work-around though. I had made myself a hot cup of ginger tea, trying to kill the taste, but instead I drank it too hot and scalded my tongue. Suddenly, the awful taste went away! So did *every* taste. But I didn’t care. It was a small price to pay for victory. I’d rather taste *nothing* than taste that horrible Ness.
I can’t recommend that approach since it’s mildly self-destructive, and since tongue scraping seems to work pretty well. But at least it’s available as a last-ditch effort if all else fails.
I had this about 3 years ago. I reported it to the FDA but they said they couldn’t track its source sine I got it from Winco’s bulk. Groceries tend to put multiple brands in the bins. WinCo blamed it on me that I ate too many. Took 3 weeks for it to go away. Thank you for posting how to get quicker relief. I have been avoiding them ever since.