Pine nuts do not taste different at that time, but after 1 to 3 days the bitter or metallic taste becomes evident and is exacerbated by the consumption of food and beverages. Symptoms usually go away after several days and there are no adverse health effects. The condition is called dysgeusia or metallogeusia and not everyone is affected. The FDA says it's not an allergy, but rather an adverse reaction to something in nuts.
Their cause remains a mystery. A lot of pine nuts have been shipped from China because they are plentiful and cheaper, but for about ten years now, a particular variety of white pine nuts grown there, Pinus armandii, has been infiltrating the packages of the good. Pinus armandii is not classified as edible by the Food and Agriculture Organization of the United Nations, and food safety experts at the European Commission consider it unfit for human consumption. Strictly speaking, they're poisonous but don't cause permanent damage, so you can still find them on the shelves of the food market.
These nuts, if you find it hard to look at them, are much shorter than the most expensive ones in Italy that we ever consume exclusively; they should be avoided. Pine nuts can also cause severe stomach pain and bleeding from the intestine. Maybe only when used with the toxic nuts of red pine, which are not edible at all, but how can you tell? You can't. Nor has an antidote or remedy been found for what was known by the unscientific name of “pine mouth”.
Unlike the world of mystery dramas in books, movies and television, solutions to mysteries in science are rarely shown within the time it takes to cook a fettuccine with pine nut pesto. Torta della Nonna (literally grandmother's cake) is a generic name for an Italian dish that in most families indicates an old family recipe for any type of cake, but is often used for a pie or cake filled with custard cream, covered with pine nuts and optionally sprinkled with icing sugar. Cases also emerged in North America, as people who had previously experienced unexplained taste alterations were now alerted to the connection with pine nuts. Chefs reluctant to give up crunch have been substituting crushed nuts, pistachios, or other nuts and seeds in their pesto, salads, and other recipes.
There are more than a hundred different varieties of pine trees and only thirty of them produce seeds that have been considered edible. It has never been identified exactly which component of Pinus armandii seeds is responsible for pine mouth syndrome and may have never been identified. European pine nuts can be distinguished from Asian pine nuts by their longer length compared to contour; Asian pine nuts are more stocky, somewhat similar in shape to long corn kernels. The Food and Agriculture Organization of the United Nations classifies these pills as unfit for human consumption; but because these nuts do not cause any permanent damage, shipments of pine nuts from China that could have pinus armandii mixed in are still available on supermarket shelves.
Then, in a small Danish trial, six volunteers consumed six to eight pine nuts of this species and all six developed a taste disorder to some extent, some much more intense than others, which began 1-2 days after ingestion and lasted approximately five days. Russia is the largest producer of Pinus sibirica nuts in the world, followed by Mongolia, which produces more than 10,000 tons of walnuts grown in forests per year. In Catalonia, a sweet treat is made with marzipan balls covered with pine nuts, painted with egg and lightly cooked, and they are called panellets. The pine nuts are then extracted as seeds and the second shells must be removed before they are ready to eat (.
I called my herbalist and my nutritionist, neither of whom had the slightest idea what could be causing this strange rash of bitterness in my mouth. In Italian they are called pinoli (in the United States they are often called pignoli, but in Italy pignolo is actually a word much more used to describe a person who is picky, too annoying or extremely meticulous) and they are an essential component of Italian pesto sauce; the rise in popularity of this sauce since the 1990s, walnut visibility has increased in the United States, mainly on the West Coast. Pine nuts are commercially available in shell form, but due to poor storage, they may have a bad taste and may be rancid at the time of purchase. .