One of the most evocative images of these dates and the low temperatures that accompany it are the embers and the white smoke that emanates from the chestnut street grill on the coldest nights of the year. Within nuts, this occupies a very special place because, although it is part of them, it has its own characteristics that make it very different, such as its low caloric value or its similarity in carbohydrates to cereals.
According to Ángeles Carbajal, professor of Nutrition at the Faculty of Pharmacy of the Complutense University of Madrid, the chestnut is the fruit of the ‘Castanea sativa’ tree that grows in humid and cool areas, which is why most of the chestnuts that are eaten in Spain They come from northern regions such as Galicia, León, the Basque Country, Asturias or Cantabria, among other.
“They have been eaten in our lands for centuriess and they came to be known as the ‘bread of the poor’ since after drying they were made into flour in areas where there were no other alternatives, since it must be remembered that potatoes and corn arrived in Spain around the 18th century”, Carbajal points out.
The teacher remembers that chestnuts are the center of ancestral traditions as the chestnut either ‘wizard‘ which is celebrated at the end of October and the beginning of November in the towns of northern Spain. They are parties that invite you to share these fruits in community and that are accompanied by symbolic bonfires and fire for their preparation.
The properties of chestnuts
Half of the chestnut is water, hence its low caloric valueand almost the other half (42-44%) are carbohydrates, mainly complex with low glycemic index and that lead to slower digestions. Chestnuts, after falling from the tree, transform their hydrates into sugars, which makes them sweeter after a week or ten days after harvesting. In the same way, when they are roasted or cooked, they become sweet due to the hydrolysis of their carbohydrates.
The chestnut has a little protein and a little fat (1-2%) but not in values as high as other nuts such as walnuts, almonds or hazelnuts, which are half made up of fats that, even healthy, represent an extra caloric intake.
Of course, this quality means that the portions taken of these nuts are smaller since the fats are more satiating than in the case of chestnuts. One hundred grams of chestnuts (about 10 chestnuts in a roasted cone) has only about 200 calories.
Regarding minerals, chestnuts contain small amounts of calcium, iron and magnesium although his greatest and most outstanding contribution is that of potassium and another of its qualities is to contain very little sodium. “This makes them a very good and healthier substitute for French fries, not only because of their low caloric value but also because of the minimal amount of salt they provide,” says Carbajal.
Vitamin C and folic acid are also notable, although when their values are cooked they can be completely lost in the first case or reduced by half in the second. Another notable component of chestnuts is their fiber content (5-8%) that can make this peculiar nut an ally in the diet to prevent constipation.
There are few studies on antioxidants, the phytochemicals present in chestnuts. Phenolic compounds, flavonoids, catechins, bioactive components with significant antioxidant and anti-inflammatory power have been isolated and are considered preventive of chronic cardiovascular and metabolic diseases such as hypertension or diabetes.
Due to its composition, the consumption of chestnuts It does not pose risks to any specific type of population except in cases of allergies or individual intolerances. When cooking them, part of their carbohydrates are converted into sugars and there are preparations such as candied chestnuts (‘marrón glacé’ in its French expression), prepared in successive layers of syrup, which do represent a significant caloric intake or restrictions for diabetics . However, raw, cooked or roasted they make a delicious and low-calorie meal between meals.
The ‘crazy’ chestnuts of the ‘false’ chestnuts
The fruit of ‘Aesculus hippocastanum’ or horse chestnut (as it is also known despite not coming from such lands) is very similar to that of the edible chestnut. It is a different tree, but due to its fruits similar to those of ‘Castanea sativa’, it is nicknamed ‘false’ chestnut.
Are chestnuts inedible due to their bitter taste They are also called ‘crazy’ despite the fact that the toxic substances that they can carry for humans would require large quantities to produce pernicious effects on the health of the organism.
“The root ‘hypo’ of the name of this tree refers to the fact that these bitter-tasting fruits and inedible by humans similar to chestnuts, they were used as feed for horses and other farm animals,” explains Carbajal.
In drugstores it is possible to find extracts or infusions of the fruits, leaves and barks of ‘Aesculus hippocastanum’ to improve blood circulation and alleviate conditions such as varicose veins or hemorrhoids.