Turmeric today is a food ingredient with global appeal. It has gone from the Indian kitchen to tea frappes, all the while retaining a golden aura of usefulness in maintaining health and combating illness.
It’s Latin name is Curcuma longa which comes from the Arabic name for the plant “Kurkum’’. It belongs to the Zingiberaceae family – same as ginger. It’s importance may be understood by the existence of no less than 46 different synonyms in Sanskrit, with “harida” being the most popular.
The most well-known medicinal action of turmeric is as a powerful anti-inflammatory. In Ayurveda it finds mention both for external (face) and internal (digestive system) application.
There are four types of turmeric mentioned in Ayurveda.
The most commonly used variety is Curcuma longa (Kannada- Arisina; Tamil – Manjal; Hindi: Haldi). It imparts a vivid yellow colour along with distinctive flavour. Mixed in sweetened milk, this turmeric is an easy home remedy for symptomatic relief from common cold and cough.
Amragandhi Haridra, mango ginger (Curcuma amrada), is another variety. The rhizomes are similar to common ginger but when snapped into two, a heavenly raw mango smell is released. When cooked, a subtle raw mango taste can be perceived. Mango ginger is seasonal and usually available from October to December. It prefers moist and hot areas along the coast. It has been described for use in joint pain, itching on the skin, indigestion, cough and wounds.
Karpura Haridra or Vana Haridra (Curcuma aromatica) is wild turmeric, found in forests. Wild turmeric has a strong medicinal smell and it less colourful than regular turmeric. Wild turmeric is gentle on the skin, and popularly used in cosmetics, which also drives up its cost. It is generally avoided in cooking because it is has a bitter taste.
Daru Haridra (Berberis aristate), tree-turmeric, was likely classified as type of turmeric because the bark of the tree, which is medicinally useful is yellow when peeled away. Taxonomically however it doesn’t belong to the ginger family. The fruit of this plant is edible and a rich source of vitamin C. The bark is used in many formulations long with regular turmeric. Medicinal uses include treatments for wound healing, eye disorder, skin disorder, diabetes and urinary tract diseases.
The dried turmeric powder which is used in homes comes from Curcuma longa (synonym: domestica). The Indian Food Composition Table, our go to reference for the nutritional properties of all commonly consumed Indian foods, highlights an interesting nutritional property of turmeric – high Iron and Vitamin A content! Because 100g of turmeric has ~ 46mg of iron, it can be considered an iron-rich food. The recommended daily allowance (RDA) for iron, by the National Institute of Nutrition, India’s premier nutrition research and policy institute, is 21mg a day. But it’s difficult to consume 50g or 10 teaspoons of turmeric a day!
Another interesting aspect of dried turmeric powder is how it is generated. There are two important steps for turning fresh turmeric into turmeric powder: curing and drying. The traditional method employs uses boiling in water as a curing step, while alkaline water is used in contemporary industries. After curing, the rhizome is dried in the sun (10 days), under a shade net (12days) or in an industrial oven at 600C (2 days). The dried turmeric is polished to reduce its coarseness and then finally powdered. Often sun-dried turmeric is reddish in appearance but behaves similar to oven-dried turmeric when added in curries and during cooking. This paper reports that the level of essential oils does not change significantly between various processing methods.
Turmeric is an ancient inclusion in the Indian diet. Scientists researching the Harappan civilisation were able to reconstruct what they ate based on chemical signatures detected in their earthenware pots. A major ingredient was, you guessed it, turmeric. If you fancy making a proto-curry, try out this recipe.
Authors: Dr. Somya Saxena, Sr Research Fellow, CAB&HN, and Dr. Megha, Assistant Professor, CAB&HN
© 2018 TDU, Bengaluru.