Sweet chestnut (botanical name, Castanea sativa) belongs to the species of flowering plants of the botanical family Fagaceae. The sweet chestnut normally grows up to a height of 100 feet and it is a deciduous (trees that shed leaves at fall) variety. The leaves of this tree are oval, jagged, pointed, green and glossy on the upper surface, while the side underneath is much paler. The tree produces light yellow hued male flowers during June that emerge in erect catkins or clusters. On the other hand, the female flowers have a green hue and grow at the bottom of the male clusters. Alternately, the female flowers also appear in detached encompassing catkins. The nuts produced by sweet chestnut are contained in a wooded, prickly burs whose color turns brown when ripened.
In present times, when you find sweet chestnut vendors on the city streets, you may take this as a definite indication of the fact that winter is on its way. Many years back, these sweet, glossy nuts not only provided an energetic snack, but were also one of the main food sources for the rural poor in the southern regions of Europe. In effect, southern Europe was the place where one would find thick forests of the sweet chestnut trees in abundance. The nuts of this plant enclose rich amounts of starch, natural oils and a number of vitamins, including vitamin B1, vitamin B2 and vitamin C. The nuts of sweet chestnut tree may be consumed in a number of ways. They may be roasted or boiled or alternately pounded into flour form and used for congealing soups or baking breads and cakes. According to the ancient Greek physician Dioscorides, the sweet chestnut tree is also a very valuable source of natural medicines that have the aptitude to cure a number of medical conditions.
The leaves, bark, twigs and also the flowering catkins and the prickly pods enclosing the nuts of sweet chestnut possess astringent properties and, hence, they may be employed to control hemorrhages, alleviate diarrhea and also promote healing. An herbal tea prepared with the leaves of sweet chestnut tree is also known to provide comfort from the aggravated mucous membranes, which, in turn, helps in providing relief from the symptoms of any cough caused by irritation, especially whooping cough.
In fact, European colonists in North America ought to have been thrilled to discover an associated species, called Castanea dentate, also known as the American chestnut, which also possessed all the qualities of Castanea sativa (sweet chestnut). However, it is unfortunate to note that by the end of the century, a deadly fungus disease walloped the great American chestnut forests and destroyed them completely. As a result of this, the species C. dentata has become infrequent these days.
Leaves, bark, twigs, nuts.
People have been cultivating sweet chestnut (Castanea sativa) for more than 2000 years now, mainly for the trees' edible, starchy nuts. There was a time when these nuts formed the staple food for the rural poor inhabiting the southern regions of Europe. Even to this day people enjoy the chestnuts as a delicacy. Traditionally, sweet chestnuts were pounded into flour or a crude meal.
European chestnut is also taken for therapeutic purposes, especially for treating medical conditions, such as breathing problems as well as digestive tract problems, counting conditions like nausea, diarrhea, bloody stools and different other stomach complaints.
Sweet chestnuts are also used for other remedial purposes, including treating disorders having an effect on the legs and blood circulation, infection, fever, kidney problems, swellings, muscle aches, disorder of a connective tissue known as sclerosis and distension of the lymph nodes owing to tuberculosis infection. An infusion prepared with the leaves of sweet chestnut helps to cure bronchitis, whooping cough, as well as blockage of the bronchial passage. When used internally, this infusion constricts the mucous membranes and slows down racking coughs. Similarly, a decoction prepared with the leaves or bark of the tree is equally helpful when used as a gargle to cure tender throats. In addition, the leaves of sweet chestnut tree are also employed in treating rheumatic conditions, stiff joints or muscles and lower back pain.
The nuts produced by sweet chestnut trees are large in size, have a brown hue and are glossy. Chestnuts are edible and may be used in a number of ways. It is best to consume chestnuts after boiling them or in roasted form. The preparation entails boiling the whole nuts in their shells/ pods for approximately 30 minutes and when they are cooked, remove the supple shell by cutting it and scoop out the kernel. If you prefer roasting chestnuts in an oven or an open fire, ensure that you perforate the external shell with a view to thwart the nuts from exploding. When the nuts are roasted, get rid of the external shell as well as the internal bitter flavoured skin prior to consuming the kernel.
The terse skin enclosing the seeds of the raw chestnuts is slightly astringent. It is comparatively easy to remove the skin by blanching the nuts quickly after you have made a cross opening at the end which is tufted. When the raw chestnuts are cooked, they are very delicious and when they are roasted, the chestnuts have a sweet taste and a floury consistency that is very dissimilar to sweet potato. One may consume the chestnuts roasted. Alternately, the cooked chestnuts may be used by confectioners to make desserts, puddings and cakes. In addition, the seeds of sweet chestnut are pounded into flour and used to make bread, and used as a substitute for coffee and cereal. Moreover, the pounded chestnuts are also used in the form of thickener in soups as well as for other culinary purposes, including fattening up stock.
A form of sugar is also extracted from the sweet chestnut seeds. It may be mentioned here that the Corsicans use sweet chestnut flour to make a variety of polenta, locally known as 'pulenta', while they use the chestnuts to prepare their individual type of beer. The Corsican variety of polenta made with chestnut flour is a solid product that is marketed in the form of a sweetened paste blended with crème de marron, vanilla, sweetened or unsweetened in the form of chestnut purée, also known as purée de marron. In addition, candied chestnuts are also sold as marron glacés. In ancient times, Roman soldiers were provided with chestnut porridge before they went into a battle.
Chestnuts have a nutritional value that is akin to those of wheat, barring the absence of the protein gluten (a binding agent) and, hence, when chestnut flour is used to make baked foods, they have a propensity to have holes or a brittle surface. In many regions of Europe, chestnuts form an important supply of starch even to this day. This is particularly true for the island of Corsica, where chestnut flour is fermented to make a local beer.
In addition, chestnuts are also widely used in spicy or flavoursome dishes as well as in poultry stuffing, particularly during Christmas. In several European cities, chestnuts are roasted over a barbecue and consumed as a street food during the winter months.
In addition to its therapeutic and culinary uses, chestnut is used for several other purposes. For instance, the leaves as well as the husks of the chestnut fruit are infused to prepare a hair shampoo.
As mentioned earlier, sweet chestnut (Castanea sativa) is primarily cultivated for its seeds or nuts that are edible. In addition, the timber of the trees of this species is also valuable and used for different purposes. Dating back to the Roman era, sweet chestnut was introduced in many northern regions, and afterward monks also cultivated sweet chestnut in the monastery gardens. Currently, specimens that are several centuries old may be seen in Great Britain as well as the entire central, southern and western Europe.
Sweet chestnut responds excellently to trimming and this is practiced in Britain till this day. Coppicing the trees of this species once in every 12 to 30 years helps to produce a high-quality crop of wood that is rich in tannin content. However, coppicing needs to be done according to the planned use of the wood and also the growth rate of the trees in any particular region. The tannin content in the wood makes the young growing trees hard-wearing and resilient to the use of the timber outdoors. This makes the wood of the sweet chestnut tree suitable for posts, stakes or fencing. The timber of sweet chestnut is sold as chestnut. The wood of this species has a pale hue, is firm and tough. In addition, in southern Europe, chestnut timber is also widely used to make barrels (occasionally used to mature balsamic vinegar), furniture as well as beams for the roof.
It may be noted that chestnut timber is not often used in large pieces since the older wood has a penchant to crack and deform badly as well as getting brittle to a certain extent. The density of chestnut timber is about 560 kg for every cubic meter of the wood and owing to its hardiness in ground contact, wood of this species is frequently used for outdoor purposes, for instance fencing. In addition, chestnut wood is also an excellent fuel. However, it is not preferred for open fires as it has a propensity to shoot out.
While sweet chestnut is indigenous to the Mediterranean region, Asia Minor as well as the Caucasus (the geopolitical area along the border of Europe and Asia), this species is now found growing in the wild all over Europe, counting Britain. The tree is primarily cultivated for its wood and the nuts, which are harvested during the autumn. Sweet chestnut is propagated from its seeds and it may take as many as 20 years or even more for a tree of this species to bear fruits. However, when a grafted cultivar, for instance 'Paragon' or 'Marron de Lyon', is planted, it starts bearing fruits within a span of just five years. Both these cultivars of sweet chestnut produce fruits that have a solitary, but large kernel, instead of the average two to four relatively smaller kernels yielded by the fruits of plants that are propagated by sweet chestnut seeds.