Cooking Oils for Indian Food
One of the most important things that will affect the flavour of your Indian food are the cooking oils that you use.
The two most common cooking oils in Indian food are ghee and mustard oil. Others which are used are those of coconut oil, peanut (groundnut) oil and sesame oil (gingelly, til). Modern arrivals are sunflower oil, rapeseed (canola) and soybean.
A word about Smoke Points
The smoke point is the temperature at which any fat starts to smoke (guess what the flame point is).
Apart from the taste, the advantage of all the cooking oils used in Indian cooking is that they have very high smoke points (above 232C/450F) this means that meat and other ingredients will 'seal' very quickly when cooked.
A high smoke point is particularly important for deep frying which is a high temperature operation - this is why all good fish and chip shops use palm oil rather than standard vegetable oil - it has a higher smoke point.
Nearly all cooking oils should not be heated to smoking as this impairs both the flavour and the nutritional values. (At the smoke point, the fat breaks down into glycerol and free fatty acids).
Mustard oil on the other hand is unique in that should be heated till it just starts to smoke. This actually improves both the flavour and the nutritional values.
Mustard Oil
This is used almost as much in Indian cooking as ghee, and is the product of pressing mustard seeds. It is used a great deal all over northern and eastern India and in Pakistan and Bangladesh. It used to be even more commonly used before the advent of cheaply produced alternatives such as rapeseed oil.
It has a strong cabbage like smell and tastes hot and nutty when raw. When heated just to its smoke point, the flavour mellows becoming sweeter and slightly hot.
As well as being used as a cooking oil, it is used in pickles, and, like ghee, it also has a cultural significance being used as fuel in clay lamps at Punjabi weddings and in the festival of Diwali.
Unlike ghee, it has only 12% saturated fats and is largely composed of mono-unsaturated fats (60%) and polyunsaturated fats (21%). It is also high in Omega-3, contains anti-oxidants and is used as a preservative. Once reckoned unfit for human consumption in America, it is now reckoned to be one of the healthiest cooking oils there is.