The chestnut is the fruit of the chestnut tree, round and flat in one of its sides, usually bright brown outside and with a white-yellowish, sweet pulp. It is usually consumed roasted, although there are many other uses and ways to present them in the market.

The great amount of minerals that chestnuts contain makes them suitable to fortify the brain and to improve all the intellectual functions of the human being; however, when eaten in great quantities, they may cause indigestion, so it is recommended not to eat more than fifteen chestnuts a day. There is a Spanish saying that recommends cooked chestnuts in autumn and winter to prevent depression.

The chestnut is the fruit of the chestnut tree, round and flat in one of its sides, usually bright brown outside and with a white-yellowish, sweet pulp. It is usually consumed roasted, although there are many other uses and ways to present them in the market.

Chestnuts can be consumed fresh, roasted or cooked; peeled or frozen to be cooked, for example, with Brussels sprouts, with the Christmas day turkey in England, etc.; or intended for industrial processing, in confectionery, manufacture of flour, which is highly appreciated for its aroma and low gluten content; in wine or liquor; purees and jams; and, over all, for the processing of the well-known marron glacé or frosted chestnuts, that is to say, prepared as jam, covered with crystallized sugar. Thanks to their resistance when dried, the peeled, cooked and dry chestnuts are used all the year round for many cooking applications.

The chestnut has a high content in glucids, 36.6 to 39.8g and it is very energetic, supplying between 170 and 182kcal per 100g of edible weight.

The chestnut is usually round and in some cases flattened in one of its sides. The colour varies depending on the variety, reddish- brown, intense and bright. The pulp has a yellowish white colour and a sweet and pleasant taste. Originally, chestnuts are covered with a hard and prickly bur that contains from 1 to 5 fruits.

There are many varieties, but one of most important and representative is the Castaño Español (Castanea sativa), known worldwide. The harvesting starts in September and during this month they are found in all the markets. But the greater consumption of this fruit is in December, perhaps due to the traditional customs in some Mediterranean areas.

The chestnut tree is a tree of majestic habit that lives for many years and reaches up to 30m of height. The leaves are deciduous, although once they dry they stay in the tree for a time.

This tree belongs to the Fagaceous family and the Castanea genus and its wood is highly appreciated in the construction field, since it is very strong and resistant.

When the tree is young, the bark is reddish-brown and smooth, turning into grayish- brown, thick and deep groovy when it ages.

The root system is strong and slightly deep, of erect growth habit.

The leaves are simple, alternate and deciduous, although they remain in the tree for certain time after their drying. The petiole is short and the blade is elliptical-lanceolate, with sawed edges. The size and the colour of the leaves vary depending on the different varieties and there is always a difference between the upperside, which is bright green, and the paler reverse.

The masculine and feminine flowers are separated; the masculine flowers gather in yellow catkins and the feminine flowers are placed in the base of the masculine catkins. The fruit is achene, with a hard, bright pericarp, velvety inside. They are protected with a hard capsule or prickly bur containing 1 to 5 nuts.