FOOD SPECIAL..MUSTARD OIL

MUSTARD OIL'S POWERFUL FLAVOUR MAKES IT AN IDEAL MEDIUM FOR INDIAN COOKING

Our sense of smell is notoriously easily tired, but can be revived by smelling something strong. Professional perfumers often use coffee beans for this purpose, but if I'm in the kitchen I sometimes open a bottle of mustard oil from a ghani, a traditional Indian oil mill, and take a deep whiff of that pungent, prickly aroma, with the irresistible aftertaste —which can be so strong you actually feel you've eaten something — of good home-made pickle.

I think raw mustard oil smells delicious, but I might be in the minority here. In the past we were fine with fats that had a distinct taste and textural character of their own: the deep rich taste of ghee, the subtly sweaty aroma of coconut oil, the nuttiness of exotic oils like argan, pumpkin seed or hazelnut, flaky pastry made with lard or crumbly pastry made with butter. But at some point we seem to have acquired the notion that our cooking fats and oils should lack all character and turn into tasteless, odourless entities that ideally pretend they don't exist at all.

Mustard oil would seem to be the antithesis of that. Murky yellow, with a flavour that can be so pungent it could probably stop a charging elephant, mustard oil can seem so untamed and wild that it is no surprise to learn from KT Achaya that in the Chandimangal, a 16th century Bengali poem, "The tamasic nature of Lord Shiva is reflected in the fact that his food is cooked not in ghee, which is a luminous sattvic product, but in pungent mustard oil."

Sattvic snobbery could be one reason why, as Chitrita Banerji notes in her excellent Life and Food in Bengal, "In 19th century Calcutta, many of the great feudal families would die rather than serve food cooked in mustard oil, which was considered only fit for the poor." No doubt, such families would view the value now attached to mustard oil in traditional Bengali food as a further sign of declining times, but I'd rather see it as Bengal's progressivism that it was able to overcome faddish barriers, to focus on the real taste and health benefits of mustard oil.

Mustard oil is, of course, used across North India, but I associate it most with Bengal partly because that's where I got my first taste of it used raw. Growing up in South India, I was familiar with mustard seeds fried at the start of cooking, which makes them nutty and slightly bitter, but not hot. So when a fellow student at IIM Calcutta made me try some jhal-muri I just thought I was getting some Bengali bhel puri, and wasn't prepared for that lick of sinus-stirring heat that exploded from the mixture of puffed rice and onions. Despite the similar structure, this wasn't bhel puri at all, and the reason was that drizzle of mustard oil that I had hardly noticed the jhal muri maker putting on at the end. After that I was addicted. I happily experienced the homely satisfaction of mashed potatoes and other vegetables mixed with a little raw mustard oil. Fish, fritters, omelettes and luchis fried in it made me realise that mustard oil had multiple personalities. Most of its uses involved heating it, which denatured its pungent chemicals, though never entirely. You would think it had been quite tamed, but after eating you would be aware of a phantom pungency that lingered quite pleasingly on your palate. Cooking with mustard oil was like watching a body builder play with a baby — those big muscles might be capable of surprising delicacy, yet this reminded you all the more of their latent, crushing power.

When I started cooking myself and using mustard oil, I realised that these multiple nature extended here too. Some were almost incandescent, releasing their pungent smells as you opened the bottle, whereas others were so bland they hardly had any heat. Bengali friends in the US in particular complained of the latter, which I was told was because it was blended with tasteless soya oil. But the trick, I was told, was to look in Indian stores for the real stuff, disregarding the warnings always posted on the bottle stating that it was only for external use, like massages or oiling your scalp and hair. That was just meant for wussy Americans who couldn't believe that something that smelled so strong wasn't dangerous.

The smell, though, is just part of the natural chemistry of mustard, which belongs to the vast family of Brassicas, which include cabbages, turnips and other vegetables that all contain pungent chemical defences. In mustard, the chemicals are so strong they can harm the plant itself, which is why they are prudently kept in a condition where they don't become active unless crushed and moistened. This is why mustard powder is sharp to the taste, but only becomes really strong when mixed with water and left for a while. KT Achaya, in his study of ghanis, notes that while water is usually added with any seed, to help the oil separate out, for mustard oil even more is added, to help develop the sharp flavour.

These pungent chemicals are volatile though, which is why they mostly vanish on heating, and also over time. They can be isolated to create a mustard essence which is used in various degrees to flavour blander oils. There are also three main types of mustard — black, yellow and brown, all with differing levels of pungency, and all grown in India. So mustard oil pungency can vary depending on which seeds are used. It is the brown seeds, Brassica juncea, which are mostly used for oil and which have the particular flavour of pure mustard oil. The best way then to use mustard oil is to find a brand, ideally from a ghani, with a level of pungency you like, and then stick to it, always buying small quantities.

Detractors of mustard oil point to two issues — the fact that it contains erucic acid, which is said to cause problems in test studies on rats, and that it has been often adulterated in harmful ways. But the data on erucic acid is not conclusive at all, and it is possibly balanced by the high levels of linoleic acid, which contain the very healthful omega-3 acids (linseed, or alsi, has more, but it is hardly as interesting to eat). There have been some high profile cases of adulteration, but this is countered by buying from reliable brands (Vandana Shiva has also made characteristically lurid allegations about the adulteration being a deliberate ploy to encourage imported soya oils).

I am not a nutritionist or scientist, so I tend to avoid getting into scientific aspects of food. But with mustard oil I've read as much as I could find simply because, from across India, I've heard of people switching away from it for apparent health concerns. But I also think because we seem to assume these days that blander means better. Yet the truth seems to be that mustard oil is high on health benefits, lasts well (the reason it is used for pickles) and has a great, distinctive taste that is worth getting to know. Rather than reducing its consumption, it is exactly the sort of traditional Indian product we should be learning to value all the more.

VIKRAM DOCTOR ETCD

23D1211