From the arrival of autumn, when the harvest begins, until the end of winter, the chestnut It is one of the most consumed nuts in Mediterranean countries, even above the almonds
Guillermo Cásedas López
Associate Professor of the San Jorge University. Graduated in pharmacy, master’s degree in business management (MBA) from San Jorge University and doctorate in Health Sciences from USJ. During his research career he has carried out stays in several institutions at the national level (Madrid, Basque Country) and internationally (South Africa).
In Spain, for example, approximately 100 000 tons in 2022. The autonomous communities of Galicia, Castilla y León and Andalusia are the main producers.
A very nutritious delight
When temperatures drop, the chestnut trees (Castanea sativa) reach their maximum ripening period in southern Europe and Asia. While in Central European and Balkan countries It is more normal to drink typical sweets or mulled wine during the pre-Christmas period, in the most Mediterranean cities it is very common to walk and breathe in the characteristic aroma given off by the street stalls of roasted chestnuts (although they can also be eaten cooked).
Furthermore, these preparation procedures modify the sensory and nutritional properties of the food, improving its organoleptic characteristics, bioavailable nutrients and its useful life. And although it is not characterized by having essential oils, the chestnut has a composition rich in carbohydrates, fatty acids, proteins, fiber and vitamins.
To this we must add that the leaves of the chestnut tree have been used in folk medicine as an expectorant for cough treatmentantipyretic to reduce feverish processes, antidiarrheal and even as a traditional treatment against infertility.
A paragraph: Do not confuse the Castanea sativa tree with the horse chestnut (Aesculus hippocastanum), although both produce fruits that are usually called chestnuts. Typical of the Balkans, the latter produces a round, shiny brown chestnut, also inside a spiny capsule, but it is not edible and may cause digestive upset if ingested.
The seeds and bark of the horse chestnut contain active ingredients with anti-inflammatory and venotonic properties that are used for the treatment of chronic venous insufficiency. This disorder is characterized by leg swellingfeeling of heaviness, pain, tiredness, itching, tension and cramps in the calves.
Health benefits
At the moment, the economic value of the chestnut is increasing not only for its nutritional virtues, but also for the beneficial health qualities it possesses.
Thus, research that has studied the byproducts of this autumn delicacy reveals a good profile of bioactive compounds with antioxidant, antidiabetic, anticarcinogenic, antimicrobial and cardioprotective properties.
Among these compounds, the organic acids and polyphenols –for example, gallic and ellagic acids–, as well as hydrolyzable and condensed tannins. In addition, they are a rich source of vitamins B, C and E, which help prevent the appearance of neurodegenerative diseases and they have a anti-aging effect.
On the other hand, it can be a food suitable for celiac people. It is gluten-free, which improves the body’s immune system response to protein.
It has also been described that chestnuts exert a prebiotic effectsince its extracts help lactobacilli (a genus of bacteria present in our body) to resist passage through the stomach, while the fiber helps the body better tolerate bile juice.
And finally, another study published by Spanish and Portuguese researchers has shown that using sustainable extraction techniques many more beneficial compounds can be discovered in the fruit of Castanea sativa.
Everything is used from the chestnut
Chestnuts are processed to become food, flour, oils, etc. through three stages: calibration, elimination of outer shells at high temperatures and peeling of the inner shells with steam and mechanical procedures. During this process, a large amount of waste material is generated, such as the inner shell, outer shell and leaves.
These agroindustrial waste can be used by other industries, such as pharmaceuticals, food, cosmetics or nutraceuticals. In the latter case, it serves as an ingredient in topical formulations to prevent and treat skin diseases caused by an imbalance in cells.
Chestnut could also be useful in textile industry; specifically, in the treatment of leather, for the manufacture of adhesives. All of these applications can increase profits, while reducing pollution and improving social, economic and environmental sustainability.
In conclusion, the chestnut is revealed to be a very versatile dried fruit. It has substances with therapeutic properties and is a very useful resource for numerous industries. However, there is still a need further research to understand its potential nutritional value and it is advisable to consume it in moderation.
This article was originally published in The Conversation.