Smell Tests

How stinky is too stinky when it comes to food?

Food
All you can smell: A customer checking a durian for aroma (Glass and Mirror CC BY-SA 2.0)

I bought a durian for a party. I had made a Filipino dish, adobo, which is chicken cooked with vinegar, soy sauce, peppercorns, and bay leaves, and had bought the durian not really to eat but to provide atmosphere, a little bit like one of those Air Wick diffusers. It’s a large south-east Asian fruit, covered in thick, heavy, spiked skin, like an ankylosaur, and it has a famously insistent smell. It is banned from public transport in several countries. The cashier at the Loon Fung supermarket wrapped it in newspaper and warned me that I couldn’t get my money back if I changed my mind.

It had never occurred to me that you might buy a durian without knowing what you were getting into, because the challenge is clear even before you crack into it. The smell of our durian filled the house for a week. To me and most people at the party it smelled pretty good, if a bit mulchy, from the start — funky and rich and complicated, fruity, a little bit caramelly, undertones of stink in a compost-vegetable way. The fruit inside, by contrast, is delicate, almost custard-like. (All-you-can-eat durian buffets are a fixture in south-east Asia.) There are around 50 discrete chemicals in durian which combine to form the confusing and, to many, offputting stench: some are sulphurous or “skunky”, some honey and fruit notes, some are savoury, described as “roasted onion”, “cooked cabbage”, “soup seasoning”.

If this doesn’t sound appealing — well, different smells affect people differently. For some the rotten-egg note of durian overpowers the more conventional fruity and sweet elements. One of my sisters loves the smell of butter, especially melted butter, and another is nauseated by it. One likes the smell of charity shop clothes. Basmati rice, to me, is one of the most delicate and fragrant smells. I gutted two partridges a couple of weeks ago and the insides smelled awful (one had inflated with a nasty gas), but the birds were tender and delicate. Civilisation is pretty much a matter of letting things go the right kind of mouldy — see soy sauce, wine, cheese, sauerkraut, and Icelandic fermented shark (hakarl, sometimes called “rotten shark”). A character in the film American Hustle describes her favourite nail polish as “perfumey, but there’s also something rotten. I know that sounds crazy but I can’t get enough of it.” It’s a metaphor, probably, but also seems to be true.

Brillat-Savarin believed that “the taste and the sense of smell form but one sense, of which the mouth is the laboratory and the nose the chimney”, that “the nose plays the part of sentinel, and always cries ‘Who goes there?’” Acquired tastes are really acquired smells — what you are doing is persuading your nose, which may not want to cooperate, that it’s safe to eat the suspect item. Strong washed-rind cheeses generally have a milder taste than you would expect. Even hakarl, which smells powerfully of ammonia, isn’t so bad to actually eat. (Icelanders have it with aquavit, which I assume blocks out the worst.) Fish sauce (nuoc mam or nam pla) smells awful if you just stick your nose into it, but in cooking it’s always cut with lime juice or diluted in broth for a deep layer of umami. (The nicest and most complex-tasting is probably Red Boat, an “extra-virgin” fish sauce, £16 a bottle from their website.)

To paraphrase the Sixties girl band the Shangri-Las, it’s good-bad but it’s not evil. Throughout life your nose learns that difficult smells won’t necessarily damage you, although your biology may be against you. Some, for genetic reasons, find that coriander tastes and smells of soap. And some people don’t have a sense of smell at all: this is anosmia, and it’s often the result of an infection or injury. Without your “sentinel”, food is depressing, confusing, and hard to see the point of. You also can’t tell you when the cake is done, when the toast is about to burn, when the milk is off. In Orwell’s Nose (Reaktion, £15), John Sutherland shows how crucial scent-impressions were to Orwell’s writing — boiled cabbage, damp plaster — something Sutherland only noticed when he lost his own sense of smell. We all know what bad smells are: off fish, says the American food writer M.F.K. Fisher, is not fit “even for burning”. I hate the smell of sour milk and mouldy cream and always try to get someone else to test a suspect for me. But anosmia means losing out on the smell of freshness as well, which you may not have consciously noticed. Fisher calls it “right, not dubious . . . like almost any happy clean thing”.

“Close the nose, and the taste is paralysed,” says Brillat-Savarin. You can prove this easily by getting a cold, which will make your food taste wrong, or going on an aeroplane, where the reduced pressure and low humidity will not only dampen many of your tongue’s taste receptors (salt and sweet in particular), but also dry out your nasal mucus, making it impossible to get the aroma of what you’re eating. There’s research which suggests noise makes food taste less sweet and less salty, and also, counterintuitively, crunchier. Heston Blumenthal, when approached to improve aeroplane meals, wanted to distribute nasal douches to passengers to counter this. The idea doesn’t seem to have taken off (sorry) but saline nasal spray is readily available in pharmacies for those catching a flight soon.

For an olfactory junkie who wants the smell without the food, The Library of Fragrance website makes eccentric single-smell scents which accurately mimic enjoyable everyday smells (£15 from their own website, or in Boots. In the US they are called Demeter Fragrance Library.) Some are more traditional (flowers, etc), many are more edgy (“Dirt”, “Play-Doh”), and in the food corner we have “Tomato”, “Cucumber”, “Pizza”, “Lychee”, and others. I am holding out for a fragrant rice one, or perhaps durian. Why shouldn’t you want to smell like something you actually like?