Chinese chestnut is one of main specialties in Dawu County, and the places of origin are some mountain areas including Xuanhua, Fengdian, Sanli, Fangfan, with annual output above 5,000,000kg, among which 3,000,000kg is from the major place of origin Xuanhua where Zhangdun Village as the “first village of Chinese chestnut” in the whole county possess annual output of around 30,000kg. Large, crisp and sweet, the Chinese chestnut contains rich protein, mineral elements and various vitamins with high nutritive value, which can be either eaten directly or cooked to eat. Any part of Chinese chestnut is of high value. Sweet and mild, its pip has the function of tonifying kidney, invigorating spleen and supplementing Qi; its shell can be used to cure stomach illness; its leaves are ingredient of astringent; its bark can be applied to cure erysipelas after being boiled; its root can be used as medicine to cure partial kidney qi. It is said that once there was a man with “waist and foot illness” who were not able to walk normally, after he was seated under a Chinese chestnut tree and ate some liters of chestnuts, he could finally stand up and walk. Clinically, anyone who is diagnosed as deficiency of the kidney and waist-leg weakness or infants who are not able to walk due to weakness of foot can eat Chinese chestnut to get cured. But when eating, you should chew it slowly and then swallow it with the fluid. The amount of chestnut eaten for one time should be appropriate. Stick to it for a long time, then you get excellent effect. There is a poem from Song Dynasty: “having suffered waist-leg illness for years ever since I get old, encountering an old man to spread the news of being cured by Chinese chestnuts, inviting him home for more details regardless of the night, finally obtaining the whit fluid of chestnuts.” In recent years, the market of Chinese chestnuts has been expected to rise, being on sales both at home and abroad. As to Chinese chestnut trees, they have been "a ready source of money". The production of Chinese chestnuts is widely spread in the whole county, and trees all over the mountains and plains create a very beautiful scene. In the spring of 2002, Dawu County has been qualified as “National Hometown of Chinese Chestnut” by the State Forestry Bureau.
Chinese chestnut is the generic term of arbor or shrub from the chestnut category of Fagaceae with 8 to 9 species. It originates from temperate area in the Northern Hemisphere. Most Chinese chestnuts are deciduous tree with the height of 20 to 40 meters, and only a small part of them are shrub. All kinds of chestnut can bear edible nuts, with single leaf in ellipse or long ellipse shape, around 10 to 30cm long, 4 to 10cm wide. The edge of leaf is setiform tooth. The chestnut is monoecism: the male flower is vertical catkin and the female flower is covered by involucres singly or in bundle. The nut is harbored in the involucres whose diameter is about 5 to 11cm covered with dense sharp spines, and there is usually 1 to 7 nuts in the involucres.
American chestnut, once the chief species in the Eastern United States, has almost been extinct and infected by some kind of fungal disease. Chestnut trees in Europe and Western Asia are also prone to infection, while chestnut trees in China and Japan can resist the fungus to some extent. So they have been introduced to America so as to cultivate antifungal hybrid species.
It is mainly distributed in Asia, Europe, America and Africa in the Northern Hemisphere. Main cultivating species include European chestnut and Japanese chestnut.
Sweet and fragrant, it contains starch about 51-60%, protein 5.7-10.7%, fat 2-7.4%, sugar, starch, crude fiber, carotene, Vitamin A, Vitamin B, Vitamin C and other mineral elements including Ca, P and Ka as well as 98% nutrient which can be absorbed by the body. Ten chestnuts contain 204 calorie with fat content less than 1g whose amount is the minimum among all fruits with shells. It is widely used for food processing, cooking, bouquet and subsidiary food. The Chinese chestnut could be eaten uncooked and fried, and could be made into fried chestnut through sugar and stirred and fried chicken with fragrance and flavor, it could be ground into powder and made into many dishes, pastry and canned food. Chestnut is easy for storage and keeping fresh, which contributes to delaying supply time in market. Chinese chestnut is produced in hilly land, called “healthy food” in foreign countries, as first-class fruit for invigorating stomach and tonifying kidney and longevity
Chinese chestnut is very precious; it could be made into dried chestnut, chestnut powder, chestnut sauce, pastry, can products and other products; chestnut soup is suitable for both the old and young, with abundant nutrition. The chestnut tree is hard with stiff material, straight texture, anti-septic and moisture proof, so it is considered as favorable material for manufacture in military industry, automotive & boats and furniture; its branches and leaves, tree skin and spur bud are rich in tannin for extracting bake gum; flower is a better nectar source. Parts of chestnut could be made into medicine, it could invigorate spleen and supplement qi, eliminate the hot and damp condition, its shell, called astringent, could cure nausea, the fried soup made from tree skin could wash erysipelas, and its root could cure partial kidney qi and other diseases
Chinese chestnuts and nuts are widely used as food in Europe, Asia and America. They are the primary source of carbohydrate of food for residents living in forests in middle ages in the Southern Europe.
Chestnut is very solid and durable, not susceptible to corrosion, with black color and beautiful pattern, and is very good decorative and furniture wood. But since chestnut grows slowly, large size chestnut is very expensive.
Tannin and tanning extracts can be extracted from chestnut bark, which is an important raw material of leather industry. Leaves can be used a tussah feed.
Chinese chestnuts shall not be eaten too many, since it is difficult to digest if eating too many raw chestnuts, and easy to subject to stagnant air if eating too many boiled chestnuts. Diabetics shall eat fewer or shall not eat, since sugar content of chestnut is very high.
Food therapy efficacy
As food, chestnut has its most popular method of application in China chestnut roasted with sugar. Blend caramel with sand and roast sand turning black with chestnut, which will make chestnuts heated uniformly and prevent sugar contained in chestnuts from losing. Roasted chestnuts are fragrant, sweet and agreeable to the taste. Steamed bread of chestnut flour is one of snacks in Beijing, it is said to be a recipe from the imperial palace, and it was appreciated by the empress dowager Cixi in that year.
Chestnut has the function of nourishing the stomach and tonifying the spleen, and tonifying the kidney and strengthening the tendon, as recorded in Compendium of Materia Medica and pointed out by Sun Simiao of Tang dynasty. Su Ziyou, younger brother of Su Dongpo ever composed a poem to praise food therapy efficacy of chestnuts. Eating chestnuts can replenish qi and blood, nourish the stomach, tonify the kidney, and strengthen the liver and spleen; raw chestnuts can cure ache in loin and legs, stimulate the circulation of the blood, and cause the muscles and joints to relax. High starchiness contained in chestnuts can provide high heat, potassium is good for maintaining normal heartbeat rhythm, and cellulose can strengthen the intestinal tract and keep normal working of the excretory system. Since chestnuts contain rich soft dietary fiber, diabetics may also taste moderately. However, it is difficult to digest if eating raw chestnuts, and easy to subject to stagnant air if eating boiled chestnuts, so it is not suitable to eat too many once. It is better to take it as snack between two meals, or eat with meals instead of after meals to avoid excessive intake of heat, which is bad for weight keeping. Fresh chestnuts are easy to go moldy or bad, and eating chestnuts going moldy will lead to poisoning, and chestnuts going bad shall not be eaten. Traditional Chinese Medicine believes that nature of chestnuts is sweet and warm, non-poisonous, and with medical functions of tonifying spleen, tonifying liver, and strengthening body. Eating raw chestnuts frequently may cure impotence in loin and legs, and the shell and bark has good astringency; fresh leaves for external use can cure scytitis; flowers can cure scrofula and diarrhea, and cure hernia once and for all. Folk remedy uses chestnut mostly. Eating one or two chestnuts in the morning and evening every day can cure kidney deficiency of the old, weak urinary frequency; raw chestnuts mashed up as mud and applied on affected part can cure traumatic injury, sore pain in muscles and bones, and have the function of relieving pain and stopping bleeding, or absorbing sepsis. It contains much starch, protein, fat, vitamin B and other nutrients, known as “king of dry fruits”. It can prevent and cure hypertension, coronary heart disease, arteriosclerosis, and osteoporosis, etc. It is also good for refractory sore in the mouth of children and canker sore of adults if eating frequently.
Traditional Chinese Medicine believes that chestnuts are available for tonifying spleen and invigorating stomach, tonifying kidney and strengthening tendon, and promoting blood circulation and arresting bleeding. It has good curative effect for deficiency of kidney energy, thereby also known as “nut of kidney”, especially suitable for deficiency of kidney energy of the old and sloppy diarrhea. It benefits for body building and disease curing if eating frequently.