Raw Mustard Oil as a Finishing Seasoning

Heat mustard oil to smoking point and it mellows: the sharp compounds volatilise and you are left with a nutty cooking fat. That is how it is used across most of eastern India, and it is why recipes tell you to smoke it first.

Assamese cooking also does the opposite. In a pitika, the oil goes in cold, raw and unheated, and everything that would have been driven off stays in the dish.

What you are actually tasting

Mustard seed contains glucosinolates. Crushing the seed brings them into contact with an enzyme that converts them into isothiocyanates — the same class of compound responsible for the burn in wasabi and horseradish. That is the sensation at the back of the throat, and it is volatile, which is exactly why heat removes it.

So the choice to heat or not heat mustard oil is a choice about whether you want a fat or a seasoning. Both are legitimate. Confusing them is what makes an under-seasoned pitika.

The pitika method

1. Boil the vegetable whole and in its skin so it does not waterlog.
2. Work with it warm, not hot and never cold — warm starch takes the oil.
3. Salt first, and mix it through before any fat goes in.
4. Add the raw oil and fold until it disappears.
5. Aromatics last — onion, chilli, coriander — so they stay distinct.

The same treatment works on fire-roasted aubergine, boiled fish, or blanched greens. Learn it once and a whole section of the repertoire opens up. Start with Aloo Pitika.