Feeding and Diet

Aichly flavored, starchy, chestnuts are popular cool season edible nuts of northern hemisphere. The nuts are native to hilly forest of China, Japan, Europe, and North America. Botanically they belong to the beech or fagaceae family of the genus: Castenea.

Castanea are very large deciduous trees. They are monoecious, bearing both male and female flowers (“catkins”), in the same tree. Castaneas have a remarkable history to narrate. The once mighty American chestnut trees were mostly wiped out by chestnut blight (Cryphonectria parasitica) early in the 20th century. A renewed interest has been growing to revive the native chestnut trees in the whole of USA.

Once pollinatation occurs, female flowers develop into large spiny burr or involucres, each enclosing 2-3 edible kernels. The fruit is quite larger compared to its peers like cashews, macadamia etc. Each nut features smooth, glossy dark brown color outer shell, 1-1.5 inch in diameter and weighing 8-12 g depending up on the species. Inside they have creamy white, sweet and starchy kernel.

Four main species of chestnut trees are being cultivated worldwide for their nuts; Castanea sativa in Europe, C. dentata in North America, C.mollissima in china and C. crenata in Japan. United States is the main importer of chestnuts from European Union, although china has been the largest exporter of nuts worldwide, especially to Japan.

Health benefits of chestnut

• Chestnuts, unlike other nuts and seeds, are relatively low in calories; contain less fat but are rich in minerals, vitamins and phyto-nutrients that benefit health.

• Nutritionally, chestnuts possess almost similar nutrition composition as that of other staple foods such as sweet potato, sweet corn, potatoes etc, consisting mainly of starch. However, the nuts also contain high quality protein.

• They are good source of dietary fiber; provides 8.1 g (about 21% of RDI) per 100 g. Fiber diet helps lower blood cholesterol levels by remove excess cholesterol absorbing in the intestines.

• Chestnuts stand out from other nuts and seeds because of their nutrition contents. They are exceptionally rich in vitamin-C. 100 g nuts provide 43 mg of vitamin C (72 % of DRI). Vitamin C is essential for formation of matrix in teeth, bones and blood vessels. Being a strong anti-oxidant, it offers protection from harmful free radicals.

• They are the one of the nuts rich in folates. 100 g nuts provide 62 mg of folates (or 15.5%). Folic acid is required for the formation of red blood cells, DNA synthesis. Adequate consumption of food rich in folates during peri-conception period helps prevent neural tube defects in the fetus.

• They are rich source of mono-unsaturated fatty like oleic acid (18:1) and palmitoleic acids (16:1). Studies suggest that monounsaturated fats in the diet help lower total as well as LDL (bad cholesterol) and increase HDL (good cholesterol) levels in the blood. Mediterranean diet which is rich in dietary fiber, monounsaturated fatty acids, omega fatty acids and antioxidants help prevent coronary artery disease and strokes by favoring healthy blood lipid profile.

• The nuts are excellent source of minerals such as iron, calcium, magnesium, manganese, phosphorus and zinc. They provide very good amount of potassium (518 mcg / 100 g). Potassium helps counter hypertensive action of sodium, lowers heart rate and blood pressure. Iron helps prevent microcytic-anemia. Magnesium and phosphorus are important components of bone metabolism.

• They are also rich in many important B-complex groups of vitamins. 100 g of nuts provide 11% of niacin, 29% of pyridoxine (vit.B-6), 100% of thiamin, and 12% of riboflavin.

• Chestnuts, like hazelnuts and almonds, are free in gluten and therefore popular ingredient in the preparation of gluten free food formulas for gluten-sensitive, wheat allergy and celiac disease persons.

• Chinese nuts (C.mollissima) are good in vitamin A; provide 202 IU per 100 g.

Selection and storage

Chestnuts are cool season crop, begin available in the markets from October through March, peaking in December. In Asia and Europe, they are still harvested and processed by traditional methods.

In the stores, choose big sized, fresh nuts. Since they are rich in starch and fewer fats than most other nuts, they tend to spoil rather quickly if exposed to air and less humid conditions for longer period. To verify freshness, cut open some sample nuts and check for heavy, meaty, creamy white kernel inside since oftentimes it is difficult to find out damaged nuts by their outer appearance. Avoid nuts with greenish mold developed between the convoluted folds and the nut kernel and its outer shell.

Chestnuts should be treated more like vegetables and fruits than nuts when it comes to their storage. Once at home; they sooner packed and kept in cold storage in the refrigerator, set with high relative humidity where they remain fresh for few weeks.

Preparation and serving methods

Chestnuts are savored for centuries by native Americans as their staple foods, used like modern day potatoes. The nuts are very sweet and flavorful.

Here are some serving tips:

• They can be eaten raw, boiled or by roasting. To roast, small incisions made over dome side of the nuts to prevent busting.

• The nuts are used as main ingredient in poultry stuffing, especially in thanksgiving turkey.

• Chestnut flour is also favored in many Tuscany recipes such as polenta, sweet breads, biscuits, cakes, soups and ice-cream.

• Marron glace is extremely popular in Europe where large sized, high quality European chestnuts (marrone di lucerna ) used. To prepare marron glace or glazed chestnuts, the nuts are soaked in water, then dipped and heated in gradual concentration of sugar-vanilla syrup for several days. Thus candied nuts are then subjected to dry under heat/sunlight before packing.

• They are also used to make chestnut butter-cream.