A little surprise, a tree that produces one of the most loved snacks in the world has been elected poisonous plant of the year 2025. It is the anaching, known for its tasty walnuts and the fruit called “Anacardio apple”. This particular primacy was conferred by the Botanical Garden of Wandsbek in Germany, which has awarded this title for 18 years, through a public vote.
But how is it possible that the anacardium, a plant that we commonly find in our dried fruit stores, can be considered poisonous? The answer lies in the fact that the real danger is hidden in the shell that envelops the anacardio walnut.
The danger hidden in the height of the anachdium
In Europe, the anacardium is known above all in the form of dry fruit, sold mainly as a snack, but the part that we consume, or the seed, is not the one that involves danger. The real risk is found in the shell of the anacardio nut, which contains a toxic substance called Cardolo. This oil can cause serious health problems if ingested. In nature, therefore, the walnuts of raw Anacardio are potentially dangerous.
To make them safe to be consumed, the anacardi are subjected to a processing process that includes the removal of the external shell, where most of the cardlo is found. Subsequently, the walnuts are toasted or steamed. These treatments destroy toxin, making the product safe for human consumption.
The Anacardio tree
The western anacardium, also known as anachard tree, is originally from the north-east of Brazil, but today it is located throughout the hot-humid tropical band. This tree is highly appreciated for its walnuts, which are actually seeds, and for its fruits, known as “anacardio apples”. Botanically speaking, the so -called “almonds” or “hazelnuts of anacardium” are not true walnuts, but they are seeds, more correctly defined as kernels.
Anacardium kernels are protected by a double shell that contains anachardous acid, a highly irritating substance for the skin. This substance chemically resembles the toxin secreted by poisonous dera, which makes the manipulation of the shells and the particularly delicate resin. It is necessary to carefully remove the shell and the resin to avoid harmful effects, especially in case of ingestion.
Despite the risk linked to the manipulation of the shells, the anachds are less allergenic than real nuts or peanuts, which is why they are generally considered safer for people with allergic sensitivity.
Anacardio is a tree that can live for several decades up to 100 years. It can reach a height of 10 meters and has leathery leaves, obovate, with dimensions that vary between 6 and 13 cm. These leaves are arranged alternately and have whole or uninterated margins. The flowers of the anochary develop in cob inflorescences, which can reach a length of 25 cm and are hairy at the touch.
The actual fruit of the anachard, or the walnut, has a shape that recalls a kidney and a color that varies from green to yellow and orange. The anacardio “apple” that is above the seed is not a real fruit, but an educated part of the plant, which is often forgotten but extremely nourishing.
Anacardio’s apple: an unknown but nutritious fruit
The anacardium is not only the walnut we know, but it is also accompanied by a particularly interesting fruit: the “anacardio apple”. This part of the plant is located between the petiole and the seed and is a false fruit, that is, it does not perform a reproductive function. Although less known in Europe, the fruit of the anachdium has a high nutritional value and deserves to be known.
Anacardio apple can be consumed fresh or transformed into juices, cocktails, jams, jellies, syrups and even wine. It is a real delight for those who have the opportunity to try it, with a unique flavor that can enrich our diet in an original way.
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