Water caltrop or water chestnut, Trapa Natans is a fruit of an aquatic weed. It has a single large white-coloured edible seed. In India it is known as singhara or paniphal. Singhara, “the only fat and gluten free nut”, is locally known as Gaer in Kashmir. It is a native to Europe, Asia, and Africa. It was first observed in North America near Concord, Massachusetts, in 1859.
Singhara is spiky triangular in shape, covered with greenish skin and a major crop for people living near banks of Wular lake located at Bandipora. The taste of this true nut is slightly sweet and starchy. It’s the crisp white-fleshed tuber eaten as such or consumed in many other forms. The skin of the kernel is hard, and makes it difficult to peel off to obtain the white edible nut inside.
In Kashmir, the importance of singhara dates back to the times of Sir Walter Lawrence, when due to floods in 1893 the main crops of valley were destroyed and due to starvation many people were suffering. At that time the flour of singhara proved to be a source of diet to those starving people. The flour of this fruit is usually eaten a substitute for cereals in India during fasting days. Singhara possess a remarkable nutritional composition. This fruit is a rich source of protein, minerals and vitamin B. Singhara 100gm contains 24gm carbohydrate, protein 2gm, potassium 584mg. It is a storehouse of phenolic compounds besides other nutrients. It forms a popular component in Chinese cuisine.
Singhara, extracted from mostly Wular lake of Kashmir, has three main varieties, namely Basmati, Dogru and Kangar. The chief variety is Basmati with thin skin and more kernel. The Dogru has a thick shell and small kernel but is a larger variety, whereas the Kangar has thick shell with long projecting horns with a very small size of the kernel. The Singhara kernels are sold everywhere in Kashmir. Kashmiri Pandits use powder of dried kernels of Singhara (Ghaarie Aut in Kashmiri ) for making puris, halwa or other items to be consumed during religious fasts and festivals.
Singhara forms an important plant in Indian Ayurvedic system of medicine as it is used in the problems of stomach, genito-urinary system, liver, kidney, and spleen. The whole plant is used in gonorrhoea, menorrhagia, and other genital infections. It is astringent, stomachic, diuretic, febrifuge, and antiseptic. During pregnancy if there is itching on lower abdomen, thigh or, breast, singhara proves beneficial. Recent studies reveal that singhara has good analgesic, antibiotic, antidiabetic and immunomodulatory properties.
Singhara has immense medicinal and nutritional values and benefits. Singhara has potential to inhibit production of inflammatory compounds, as the phenolic antioxidants scavenge free radicals in the body and prevent organ damage and pain. It has been observed that it has a potential to manage sugar levels so is a good substitute for wheat and rice. Since it is gluten free, it can be eaten by people suffering from celiac disease. Being rich in flavonoids like luteolin, fisetin, and diosmetin, it helps in slowing down damage caused by free radicals. Being rich in minerals like potassium, magnesium, zinc and copper, it retains antioxidant properties and helps in reducing of blood pressure. It has some useful minerals like iodine and manganese that help in maintaining proper functioning of the thyroid gland.
The juice of water chestnut is used to control diarrhoea and dysentery. Water chestnuts are excellent sources of potassium, a mineral that is vital for proper muscle and neural functioning. Potassium also regulates water retention and blood pressure by balancing sodium. On the basis of rich nutritional values, the benefits of water chestnuts are very effective for maintaining good health. The antioxidant activity is thought to reduce risk of cancer. The symptoms of irritable bowel syndrome (IBS) and Crohn’s disease can be sometimes reduced eating foods low in FODMAPs like singhara.
It is safe to have this nut even for those who have nut allergies. When buying raw singhara, choose one that has smooth, unwrinkled skin without soft spots. After buying water chestnuts, store them unpeeled in paper bags in the refrigerator for up to a week. You can also freeze them in suitable containers as they last up to 5-6 months at 0ºF and it’s better to peel water chestnuts just before use. Storing peeled ones in water may rob them of their fresh taste and texture. Peeled singhara stays 2-3 days but water needs to be changed every day. The best way to do so is to boil water chestnuts, peel them, pack them in freezer bags/suitable containers, and freeze. Fritters prepared from singhara are popular in Kashmir. Besides, singhara flour is utilised in making kulchas and other bakery items. Many value added products have been prepared from singhara which are good to taste and can raise the economy of Bandipora district.

The writer is Associate Professor at Division of FST, SKUAST-K, Shalimar. [email protected]

Dr Afsah Iqbal Nahvi