I made pesto for the first time on Saturday using the Rouxbe recipe. I served it with some local fresh pasta and it was awesome.

However, sometime on Sunday or Monday I started noticing a strange bitter aftertaste when eating other foods. At first I chalked it up to whatever I was eating or drinking at the time, but it kept happening with different things. (especially sweeter tasting things)

Yesterday it was bugging me so I did some searching on google and was surprised to discover that this problem has been associated recently with pine nuts. Has anybody else encountered this?

http://www.dailymail.co.uk/health/article-1184261/Pine-mouth-puzzle-Why-nuts-leave-bitter-taste.html

Thanks for the article. I haven't heard of or experienced this myself and would be curious how many others have. I have had encounters with rancid pine nuts, but that's an entirely different thing. I make sure to store pine nuts in the freezer if I can't use them quickly enough.

Too bad you have experienced this. Although it will change the flavor somewhat, you could try making pesto with other nuts such as walnuts or blanched almonds. Cheers!

How exactly would you know if pine nuts are rancid? I haven't used them a lot, but they looked and appeared normal enough. I used them the same day I got them at the grocery store, so they weren't sitting around the house for long.

Next time I suppose I'll probably try pine nuts from a different source. It's just a shame that I couldn't stand to eat the leftover pesto.

Hard to describe but you'll know. Some people say they smell sour or fishy. The oils in the nuts go off and will have a bad smell and taste. Taste any type of nut and you'll know. Also, if the raw nut is not opaque (it's turning color and darkening), this could be a sign that the nuts are old and may be rancid. I'm sure if you just bought them though, they are fine.

Instead of the pesto going to waste, you could put it in a pretty jar and give it to a family member or one of your neighbors. I'm sure it'll put a smile on someone's face :)

Hi Jerry,

Well, I have to say I fell victim to "Pine Mouth" this past weekend. I ate maybe a teaspoon of pine nuts and within 48 hours everything I have eaten and continue to eat or drink seems to have a metallic or bitter taste to it - including water! I was dumbfounded and started searching Google. Then I came across this article and it triggered my memory that you had posted this same experience a while back! Do you remember how long it lasted? And did you try any of the remedies listed in the article? It is so bizarre!

Sorry to hear that! It lasted about a week for me. I didn't try any of the remedies in that article, but tried to stay away from sweet tasting foods. They seemed to have a more pronounced aftertaste than savory foods.

One of the theories I've seen is that some of the pine nuts imported from China may include a few species not traditionally consumed by humans, so I've been sticking to nuts with a clearly identified origin on them.

Thanks for the information! I did read that. I was away at a family reunion and made the green beans with cambozola & pine nuts. I purchased the pine nuts at an Italian supermarket but didn't check where they were from. Funny thing is I have a bag of pine nuts in the freezer that I have cooked with. When this happened, I checked and they too are from China...so it must be certain varieties because I haven't been affected by those. However, in the future, I will be very careful to look at the origin.

It is a relief to know that it is temporary, but sure puts a damper on eating. Maybe that's a good thing though after all of that food at our reunion :) I might try one of those remedies to see if they work. Will let you know. Thanks again for posting this and for the reply. Cheers!