The water chestnut is often confused with the water caltrop, but the two plants are unrelated. It's not actually a nut but a grass-like, aquatic plant. The part that is used for food is the tuber, or the bulb, of the plant.
The water chestnut is popular in Chinese stir-fried dishes. It is also made into a starch commonly known as caltrop starch which is used (with other ingredients such as tang flour, a fine wheat starch) to make dumpling skins.
The flesh of a water chestnut is white and crisp, with a bland, vaguely sweet nutty flavor. It is unique from other vegetables because it stays crisp even after cooking. Water chestnuts are small in size, and may be eaten raw (as it is in many Chinese dishes), or boiled, grilled or pickled.
Selecting and Buying
Water chestnuts have a long growing season, approximately 7 months, without frost, so they can only be grown in semi-tropical places.
Preparation and Use
They can be eaten raw or added raw and sliced to salads and clear soups. In Asia they are made into a drink by either blending raw chestnuts in water or boiling them or their skins in water for 15 to 30mins and adding a little extra palm sugar to enhance the flavour. The drink tastes like water that has have sweet corn boiled in it and it is reputed to have cooling properties, popular on hot days in Asian cities.
Water chestnuts are frequently added to stir-fries, stuffings, and dumpling fillings for extra texture and a sweet flavor.jicaa
Conserving and Storing
Harvested corms can be stored in the bottom of the fridge in sealed plastic bags or containers to prevent them from drying out. There are always a few that rot during storage and need to be sorted out from time to time. This rot is often due to even slight damage to the skin during harvesting & later handling. They keep quite well in the ground where they grew while the temperature stays low enough to maintain dormancy. Dried out corms or ones that have been frozen will not grow. They also keep very well in cool damp sand. We have kept corms like this for well over a year in perfect condition.