Chapter 3 — Foods at the Edge of the World

"In fact, to eat Durians is a new sensation, worth a voyage to the East to experience." — Alfred Russel Wallace, The Malay Archipelago (1869)

S omewhere on a Baltic jetty a man is easing open a swollen tin of fermented herring, and the reek that drifts to his neighbours is, to him, the smell of the short northern summer and of every summer he can remember. Somewhere else a grandmother is halving a translucent, grey-green egg over a bowl of rice porridge for a child who has eaten it since before she can recall a first time. The foods gathered in this chapter reach the English-speaking world under a single unlovely label — extreme — and the word tells you almost nothing about the foods and almost everything about the person reaching for it. There is, on inspection, no such thing as an extreme food. There is only a food eaten somewhere you happen not to live, made by a knowledge you did not inherit, and loved by people who would find your own supermarket cheese — a curd deliberately infected with a living mould and left to soften under careful rot — every bit as strange as you find theirs. This volume made a promise in its Curiosity Mandate, and the promise governs every page that follows: to write each of these foods from the inside, as the prized cuisine of a real culture, and never as a curiosity staged for a squeamish outsider to shudder at. The organising word of the chapter is the exact opposite of endurance. It is prizing.

The distinction matters because the freak-show version of this subject always gets the verb wrong. It imagines the Icelander choking down cured shark to win a bet, the Swede suffering his herring as a test of nerve, the diner in Manila bracing against a duck egg. None of that is what is happening. These are foods that people queue for, pay a premium for, carry home wrapped in newspaper, and serve to the people they love on the days that matter. They are also, almost without exception, chemistry — good chemistry, worked out over centuries by cooks who understood the transformations in their hands long before anyone could name the molecules involved. A few of them, handled carelessly, are genuinely dangerous, and where that is true this book says so plainly and in the same breath, because the fourth clause of the Curiosity Mandate forbids describing a hazardous food without its safety truth attached. But danger is the exception here, not the theme. The theme is that millions of people, given the whole larder of the earth to choose from, have chosen these.

It helps to notice how much of any table is already built on the same principle. The coffee in the reader's cup began as a fruit whose pulp was fermented off the bean before the bean was scorched black; the chocolate beside it was heaped and left to ferment for the better part of a week before it was anything a tongue would call sweet; the bread, the beer, the yoghurt, the soy sauce, the very cheese course are all, without exception, decay steered and stopped at a chosen point. Controlled rot is not the signature of the strange table but of nearly every table, our own emphatically included. The only variable — and it is the whole of the difference — is which of those transformations a particular childhood taught you to file under delicious.

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<figcaption><em>Plate 6. A world atlas of the bold table — hákarl off Iceland, surströmming in the Baltic, casu marzu in Sardinia, the century egg across China, nattō and balut around the Pacific rim, and the durian through the equatorial forest — each food prized precisely where it is made.</em></figcaption> </figure>

The North Atlantic's Amine Larder

Begin in the cold, where the sea is generous and the growing season is not, and where preserving a glut of protein against a long winter was for most of human history the difference between a village and a graveyard. Two of the most notorious foods on any listicle — Iceland's hákarl and Sweden's surströmming — are solutions to that single northern problem, and both turn on the same family of molecules: the amines, the small nitrogen compounds that fish tissue yields as it is broken down, and that the human nose is exquisitely, unavoidably tuned to read.

Hákarl is the harder case, and the honest one, because the animal at its centre is toxic before it is food. The Greenland shark, Somniosus microcephalus, is a slow, cold, long-lived fish that solves the problem of living in deep polar water by flooding its tissues with urea and trimethylamine N-oxide, or TMAO — osmolytes that keep the shark in balance with the salt of the sea and stop its proteins from failing under pressure and cold. Eaten fresh, that flesh is genuinely poisonous: the gut's bacteria reduce the TMAO to trimethylamine, and a meal of untreated Greenland shark can bring on a violent intoxication the Icelanders drily call being shark drunk. The cure is not seasoning but chemistry given time. The flesh is pressed in drained gravel beds so its fluids can escape, and fermented for some weeks while bacteria break the urea down into ammonia and drive the TMAO down toward nothing; a study following the process through to the plate found trimethylamine N-oxide falling below the limit of detection within about five weeks as the pH climbed from roughly 6 to roughly 9.[^1] Then the blocks are hung in open, draughty sheds to dry for months more, and it is in this long airing that most of the ammonia and amine simply leaves on the wind. What remains is safe, and its knockout smell of ammonia is not a warning but a certificate: it is the audible evidence, so to speak, that the poisons have been leaving for months. To an Icelander a cube of hákarl on a toothpick, chased with a swallow of Brennivín — the caraway schnapps whose skull-marked label earned it the nickname svarti dauði, the Black Death — is heritage made edible, the taste of an island that survived on what the cold sea would give.

There is a further wonder folded into that toothpick, and it belongs in any honest account. The Greenland shark is not merely old-fashioned; it is, individual for individual, the oldest backboned animal known to science. In 2016 a team led by Julius Nielsen dated the eye-lens nuclei of twenty-eight of the sharks by the radiocarbon sealed into them at birth and found lifespans reaching at least 272 years, with the largest specimen, a five-metre female, estimated at close to four centuries — 392 years, give or take — and sexual maturity not arriving until somewhere around a century and a half. A block of hákarl set out at a Reykjavík Þorrablót, the midwinter feast of the old Icelandic calendar, may therefore be the flesh of an animal that was already swimming the deep before the island had heard of Napoleon. Icelandic makers grade the result by where on the carcass it comes from — the paler, firmer flesh of the body eaten apart from the softer, chewier, more pungent flesh nearer the belly — and the craft has its shrines, chief among them the Bjarnarhöfn farm on the Snæfellsnes peninsula, where the Bjarnason family has cured shark for generations and keeps a small museum of the drying sheds and the winches beside the fish. None of this is endurance. It is a cuisine with connoisseurship, grades and a pedigree, built on the single most patient animal in the sea.

Surströmming asks less of the chemistry and more of the nerve, though the nerve, again, is the outsider's and not the Swede's. Here the fish is the small Baltic herring, caught in spring, salted only lightly — enough to hold off outright putrefaction, not enough to stop the work — and left to ferment through the summer in the brine's own bacteria and the fish's own enzymes. The result is sealed into tins while it is still, quietly, alive: the fermentation continues in the can, salt-tolerant bacteria breathing out carbon dioxide until the tin swells into the taut, ominous drum that every photograph of surströmming shows. Open one and the gas carries the aroma out under pressure, which is why the ritual is conducted outdoors, at arm's length, and ideally underwater in a bucket. The smell has been analysed with the same instruments a perfumer might use, and it is a chord rather than a note: trimethylamine, giving the flat reek of fish left too long; hydrogen sulphide and other sulphur compounds for the rotten-egg base; and over them the sharp volatile acids — butyric, propionic, acetic — that the tongue reads, once past the nose, as the deep sour savour the Swedes prize. Served properly, in a soft flatbread called tunnbröd with almond potato, raw onion and a smear of sour cream, it is not an ordeal but a late-summer feast, eaten in company, in daylight, with schnapps and a great deal of laughter. As Volume I argued of umami, the nose and the tongue do not always agree, and a cuisine can be built precisely in the gap between them.

The herring's sourness, it is worth insisting, is not the sourness of spoilage but of design, and the design has a paper trail. Surströmming appears in the Swedish written record by the sixteenth century — herring of this kind figures among the preserved fish that Gustav Vasa's crown levied in tax from the northern coasts in the 1540s — and the reason is economics as much as taste: salt was costly and heavily taxed, and a fishing village that could not afford to pack its catch in the usual weight of it learned instead to preserve the herring with only a light brine and the fermentation the brine allowed. What the low salt permits is a specific cast of microbes, the salt-tolerant anaerobes of the genus Haloanaerobium chief among them, which turn the fish's own sugars and compounds into the acids and gases that both keep it and flavour it. The souring is a preservative; the swelling can is the fermentation still at work; and the tradition is regulated to this day down to the calendar, the fresh tins released each year, by long custom, no earlier than the third Thursday of August. A food that half the internet files under rotten is, at home, a seasonal event with an opening night.

The Honest Danger of the Far North

Farther north still, past the last tree, the cold larder turns to a food that carries the Curiosity Mandate's fourth clause on its face — a genuine delicacy that is also, prepared wrongly, genuinely lethal, and that must therefore be written with both truths held together. Kiviaq is the winter dish of the Inughuit, the Polar Inuit of Avanersuaq in the far north-west of Greenland, and it begins each summer with a glut: the little auk, Alle alle, a plump sparrow-sized seabird that breeds in the scree slopes of the high Arctic in colonies of staggering size, millions of birds wheeling off a single hillside. When the auks are fat, the hunters take them in nets by the hundred, and as many as several hundred whole birds — feathers, beaks and all — are packed into the emptied, blubber-lined skin of a seal, the air pressed out, the seam sewn tight and sealed with fat to keep the flies off, and the whole heavy parcel laid under a cairn of stones on the cold ground to ferment for anything from three months to a year and a half. The birds break down slowly in their airless, chilled skin into something sharp, cheese-like and deeply savoury; when the parcel is opened in the dark of winter the auks are eaten more or less whole, the fermented flesh pressed from the skin, and the dish belongs above all to celebration — to birthdays, to weddings, to the midwinter gatherings that break the polar night. It is not a stunt or a hardship ration. It is festival food, and it is the rational harvest of a bird that arrives in numbers no other method could hope to store.

The danger is equally real, and the honesty this book prizes requires it in the same breath. Fermentation in a sealed, airless, cold parcel is precisely the condition under which Clostridium botulinum — and in the Arctic marine world especially its cold-tolerant type E, common in the guts of seals and the sediments of those waters — will grow and shed its paralysing toxin if the birds are not fresh, the skin not truly airtight, or the temperature not reliably cold. When the method is followed, generations of practice keep it safe; when it is not, the result is botulism, and the record is not hypothetical. In 2013 a cluster of deaths in the settlement of Siorapaluk was traced to a batch of kiviaq made not with auks but with eider ducks, which do not ferment in the same clean way, and those who ate it were poisoned. Tradition, too, lays the death of one of the Arctic's most celebrated explorers at this table: Knud Rasmussen, the Greenlandic-Danish father of Inuit ethnography, fell ill during his Seventh Thule Expedition and died in Copenhagen in December 1933 after what was recorded as food poisoning — a rare botulism, by one account — followed by pneumonia, an illness his biographers have long associated with a meal of kiviaq, though the attribution is remembered as much as it is proven. The dish is not thereby condemned; the peoples who make it correctly have eaten it safely for centuries, and it remains a treasured food. But it stands as the chapter's plainest lesson that the knowledge is the safety — that these foods are the property of a craft, and that the craft, not the daring, is what makes them fit to eat.

Lye, Ash and Brine

Move south and inland, and the transforming agent changes from the amine to the alkali, and from the fish to the egg. The Chinese century egg — pídàn, 皮蛋 — is among the most maligned foods in the Western imagination and among the most ordinary at a Chinese table, spooned into rice congee for breakfast or sliced cold over silken tofu, an everyday thing sold in every market. Its name promises rot and its method delivers the opposite: a controlled, waterless cooking by pH. Raw duck or hen eggs are packed in a paste of wood ash, slaked lime, salt and tea and left for weeks to months, during which the strong alkali of that coating — chemically, the caustic soda thrown off when lime, soda ash and water meet — soaks through the shell and raises the egg's interior to a pH somewhere between 9 and 12. At that alkalinity the proteins denature and set without any heat at all: the white turns to a clear, amber, quivering jelly, the yolk to a dense grey-green heart smelling faintly of ammonia and sulphur, the whole egg deepened and darkened by slow, cool browning reactions. The connoisseur's mark of a well-made one is a scatter of pale, feathery crystals across the surface of the set white — the songhuā, or "pine-flower", pattern that gives the egg its other name, and which chemistry identifies as needles of the amino acid tyrosine, crystallising out of the broken-down protein as a sign that the cure has gone exactly as far as it should. It is denaturation, in other words, treated as an art, and prized for the same reason a good cheese or a good ham is prized: because a cook learned to steer decay toward delight. The English name "thousand-year egg" is a shopkeeper's flourish — the cure runs to weeks or a few months, never centuries — but it keeps hold of the right intuition, that time and alkali together can carry an egg somewhere no amount of heat would ever take it.

Here the safety truth belongs, quietly and without alarm, because the century egg carries one and modern practice has answered it. To close the pores of the shell against oxygen and to steady the alkaline set, some traditional makers added a little lead oxide — litharge, the yellow huángdān of the old recipes — to the curing paste, and the price of that shortcut was a measure of lead carried into a food eaten by children at breakfast. The trade has largely put the practice behind it. Reputable modern producers make what the Chinese label calls wúqiān, 无铅, "lead-free," pídàn, substituting harmless zinc oxide for the lead and holding the finished egg below China's regulatory ceiling for the metal; the eggs on a well-run grocer's shelf today are cured to that standard and are simply safe. The honest note is only this: the century egg to buy is the lead-free one, and it is the ordinary one — a reminder that the craft of a bold food includes, as it always has, the steady correction of its own hazards.

The same alkaline principle travels north and lands, of all places, on the Christmas tables of Norway, Sweden and the Lutheran Midwest of America as lutefisk. The starting point is stockfish — cod dried hard as a board on the racks of the northern coast — and the transformation is frankly caustic: the dried fish is first soaked back to life in water, then steeped for days in a lye of sodium hydroxide, the same strong alkali that scours drains, until the flesh swells and the pH of the fish climbs toward 12. At that alkalinity the cod's proteins unfold and re-knit into new cross-links, and the once-rigid fish turns translucent and trembling, a pale grey jelly quite unlike anything a plain soak in water could produce. Then it is rinsed at length in fresh water to carry the causticity back down — the finished dish still sits above pH 10, alkaline enough to make it faintly slippery and famously delicate — and gently cooked. There is real chemistry to respect in the timing: leave the fish too long in the lye and its fats begin to saponify, turning to soap in the most literal sense, which is the origin of the old Scandinavian-American warning against buying the cheap lutefisk from a maker who hurried or overran the bath. Prepared with care it is a soft, mild, buttery thing, eaten with white sauce and potatoes and a great deal of affectionate grumbling, the centrepiece of a church-basement supper from Trondheim to Minnesota — proof that the alkaline larder is not a foreign curiosity at all but a northern European inheritance, hiding in plain sight under a blanket of melted butter.

Alkali does the work in the egg and the cod; brine and its microbes do it in the food that may out-smell them both. Stinky tofu — chòu dòufu, 臭豆腐 — is the beloved night-market snack of Taiwan and much of China, firm tofu steeped in a fermented brine and then most often deep-fried golden and served with pickled cabbage and a garlicky, chilli-bright sauce. The brine is the heart of it, and it is a living heirloom: a chòu lǔ built from fermented greens, and depending on the maker milk, shrimp, bamboo shoots and herbs, kept and topped up over months or years like a sourdough starter, teeming with lactic-acid bacteria, yeasts and moulds — Yarrowia, Bacillus, Lactococcus and their kin — that between them take the tofu's bland soy protein apart. What they leave behind has been read off the instruments as precisely as the durian's perfume: a gas-chromatographic analysis of stinky-tofu brine turned up some thirty-nine volatile compounds, led overwhelmingly by indole — the same molecule that at a whisper gives jasmine its sweetness — trailed by dimethyl trisulphide, phenol and dimethyl disulphide, the indole and its cousin skatole born from the microbes' work on the amino acid tryptophan, the phenol and p-cresol from tyrosine and phenylalanine. It reads, on paper, like an inventory of everything the nose is built to flee. And yet the fried cube that comes of it is crisp-shelled, custard-centred, sharp and savoury and utterly ordinary, sold from a thousand stalls to people who are not being brave. Once again the molecules that alarm the newcomer are the exact ones the initiate has learned to read as supper.

The Living and the Loved

Sardinia carries the idea of steered decay to its most vivid, and most legally awkward, conclusion. Casu marzu is a sheep's-milk pecorino that has been opened to the cheese fly, Piophila casei, and given over to its larvae; as they feed, the enzymes of their digestion break the cheese's fats down into something soft, weeping and intensely piquant, a step past the ordinary sharpness of a mature pecorino into a realm the island has valued for generations. It sits, at present, in a genuine legal limbo, and honesty requires the whole of it: the cheese cannot lawfully be sold in the European Union, whose food-safety rules admit only produce fit for consumption, and it has been off the open market on those grounds since 2002 — yet Italy also lists it among its recognised traditional agri-food products, so that a thing officially prohibited is at the same time officially treasured. The safety note is real and belongs here: the larvae are eaten alive, and there is a theoretical risk that they might survive ingestion to cause an intestinal upset called pseudomyiasis, though no case has in fact been tied to the cheese. Sardinians who make and eat it are not courting danger; they are keeping faith with a pastoral craft older than the regulations that now trouble it, and this book records it with the respect due a delicacy, not the shudder invited by a stunt.

It is, admittedly, the most theatrical delicacy in the chapter, and the theatre is worth reporting accurately rather than luridly. The larvae of Piophila casei are translucent, a few millimetres long, and startlingly athletic: disturbed, they can flick themselves as far as fifteen centimetres into the air, which is why diners old to the cheese eat it with a certain care, and why Guinness World Records, reaching for a superlative in 2009, crowned casu marzu the world's "most dangerous cheese." The reputation runs ahead of the reckoning. What Sardinia is doing is only the same thing every great cheese does — inviting a microbe or a mould to carry milk somewhere new — pushed one taxonomic step, from mould to fly, further than the rest of Europe was willing to follow. The result is a cheese so soft it is spread, weeping and peppery, on the island's thin pane carasau and washed down with a hard red wine, at the tables of people for whom it is not a dare but the sharp, particular taste of home.

Two more foods of the Pacific rim deserve their proper place, for the same reason and in the same spirit, and each is somebody's plain and daily breakfast. Japan's nattō — soybeans fermented by the bacterium Bacillus subtilis var. natto into a sticky, cobwebbed, ammoniac tangle, traditionally by wrapping steamed beans in rice straw and holding them near forty degrees for a day — is eaten by millions over hot rice with mustard and a raw egg, and it is a small marvel of biochemistry. The famous threads that stretch and cling between the beans, the ito-hiki, are not slime but a polymer, poly-γ-glutamic acid, spun by the bacterium as it works; the same fermentation makes nattō one of the richest known dietary sources of vitamin K2 in the form of menaquinone-7, the longest-lived form of that vitamin in the blood and the one that best directs the body's calcium into bone and away from the artery walls. And it was in nattō, in 1980, that a Japanese researcher named Hiroyuki Sumi — hunting through more than a hundred and seventy natural foods at the University of Chicago for something that might dissolve a clot — dropped a little of the sticky bean onto a dish of artificial fibrin held at body heat and watched the clot melt away within hours. He named the enzyme responsible nattokinase, and a breakfast eaten in Japan for centuries acquired a second life in the cardiovascular literature. The Japanese themselves attribute nattō's discovery to a happier accident: the legend has the eleventh-century warrior Minamoto no Yoshiie, on campaign in the snowbound north-east, hurriedly stuffing boiled soybeans meant for his horses into straw bags, opening them days later to find them fermented, and eating them anyway with approval. The tale is tradition rather than record, but it keeps faith with the truth that every one of these foods began as a glut, a delay and a cook brave enough to taste the result.

The Filipino balut completes the round, and it is an evening ritual as much as a food. A fertilised duck egg — from the hardy native itik, the Philippine mallard — is incubated for a little over a fortnight, then simmered and eaten warm from the shell, and the exact day of incubation is a matter of considered local taste: in the Philippines the egg is usually taken at sixteen to eighteen days, when the duckling is still soft and pale and largely unformed within its broth, while the Vietnamese hột vịt lộn is allowed to run to nineteen or twenty-one days, by which point the bird is recognisable and its little bones firm but tender under the tooth. The proper way to eat one is to crack the top, sip the warm sabaw — the savoury liquid around the embryo — and then work down through yolk and duckling with nothing more than a pinch of salt, a splash of spiced vinegar, sometimes a bite of chilli. It is rich, warming and frankly nourishing, some fourteen grams of protein and a good measure of calcium in a single palm-sized shell, and it is sold each dusk by vendors calling the word down the street to office workers and night-shift drivers who grew up on it. To them it is no more a test of nerve than a soft-boiled egg is to anyone else. That, and not its strangeness, is the fact worth keeping: every food in this section is somebody's ordinary evening, somebody's ordinary morning, loved into being by the people who solved a problem with it.

The Perfume of the King

The boldest food in this chapter is not a ferment at all but a fruit, and it is loved on a scale the others cannot approach. Across Malaysia, Indonesia, Thailand, Singapore and the whole equatorial belt of Southeast Asia, the durian — Durio zibethinus, from duri, the Malay word for thorn — is crowned without argument the King of Fruits: a spiked, football-sized weight of custard so desired that whole orchard economies and connoisseur lineages of named cultivars have grown up around it, and so pungent that Singapore forbids carrying it on the underground and hotels across the region post the little crossed-out silhouette on their doors. The two facts are not in tension. They are the same fact, seen from the nose and from the tongue, and the durian is the purest illustration this book can offer of prizing over enduring — for the people who love it are not tolerating the smell to reach the flesh; they are, many of them, in love with the smell too.

That love has built both a canon and an economy. The durian is not one fruit but a connoisseur's alphabet of named cultivars, argued over the way a wine list argues terroir: Thailand's Monthong, pale and mild and meaty, is the export king, making up something like ninety-five per cent of the fresh durian Thailand ships abroad; Malaysia answers with Musang King — Mao Shan Wang, the bittersweet, custard-dense clone that fetches the highest prices of all and has been dubbed, in the Chinese market now chasing it, the "Hermès of durian" — with the older, golden-fleshed D24 close behind. The trade those names ride on is vast and startlingly young. China has become the overwhelming buyer, taking billions of dollars of fresh durian in a year and, in one recent season, some ninety per cent of Thailand's entire fresh-durian export, so that whole provinces of orchard now lean toward an appetite that a generation ago scarcely existed; a single Musang King on a Shenzhen counter can cost several times the Monthong beside it. The premium, worth marking, is paid not in spite of the smell but for a particular grade of it. Prizing, in the durian's case, comes with a price list.

Alfred Russel Wallace, who ranks with Darwin at the head of Volume V's cast of travelling naturalists, met the durian in Borneo and gave it the praise that stands as this chapter's epigraph, ending a long and careful description with the verdict that to eat it was "a new sensation, worth a voyage to the East to experience." He was right about the sensation and, it turns out, right to reach for the word new, because the durian's flavour is a genuine paradox that the chemistry has only lately explained: it is fruit and savoury at once, sweet custard and fried onion in the same spoonful, and the mouth cannot quite file it under either heading. The fruit and the funk hand this chapter forward to its closest study.

Field Note — The Durian

Hold a spoon of ripe durian under a good instrument and the contradiction resolves into two families of molecules working at once. On one side sit the esters — the fruity, estery notes any orchard makes, among them ethyl (2S)-2-methylbutanoate, which reads as clean tropical fruit, and a whisper of honeyed ethyl cinnamate. On the other sit the volatile sulphur compounds, the thiols and di- and tri-sulphides — diethyl disulphide, diethyl trisulphide, ethanethiol and their kin — that carry the notes anyone who has stood near a split durian will know: roasted onion, boiled egg, warm garlic, a hint of struck match. A careful odour analysis of the Thai 'Monthong' cultivar found both families among the fruit's most powerful odorants, a fruity-sweet chord and a savoury-sulphurous one sounding together; the nose, built to keep sulphur and sweetness in separate mental drawers, is simply not equipped to meet them in one mouthful, and reports the collision as astonishment.

Why should a fruit go to such lengths to make sulphur? In 2017 a team sequencing the durian genome found the answer written in the DNA. The durian carries an expanded family of the gene MGL, methionine γ-lyase, and switches it sharply up as the fruit ripens — an enzyme that works on the sulphur-bearing amino acid methionine to throw off exactly the volatile sulphur compounds the aroma is built from. The fruit is, in the most literal sense, genetically tuned to broadcast that smell, and the reason is seed dispersal: in the forest the durian drops when ripe and trusts its carrying reek to summon the big mammals — orang-utans, elephants, civets, deer, even tigers — that will move its seeds. The smell that empties a train carriage in Singapore is a signal perfected to fill a rainforest. The devotion and the ban-signs are two human responses to one ancient message never meant for us at all — which is, when you think of it, worth a voyage to the East to consider.

<figure> <svg xmlns="http://www.w3.org/2000/svg" width="100%" viewBox="0 0 460 620" role="img"><title>DURIO ZIBETHINUS — the King of Fruits, with cutaway of the arils</title>  <rect x="11" y="11" width="438" height="598" fill="none" stroke="#43331f" stroke-width="1.3"/> <rect x="18" y="18" width="424" height="584" fill="none" stroke="#43331f" stroke-width="0.6"/> <path d="M28 28h18M28 28v18M432 28h-18M432 28v18M28 592h18M28 592v-18M432 592h-18M432 592v-18" fill="none" stroke="#b5502a" stroke-width="1.3"/>  <g fill="none" stroke="#43331f" stroke-width="1.2" stroke-linejoin="round" stroke-linecap="round"> <path d="M221 94L220 74L238 74L237 94M220 80L238 80"/> </g>  <path d="M228 96L208 122L188 104L176 140L150 128L150 166L118 168L128 204L104 232L130 248L110 286L140 292L150 330L170 320L176 356L200 344L214 374L228 356L242 374L256 344L280 356L286 320L306 330L316 292L346 286L326 248L352 232L328 204L338 168L306 166L306 128L280 140L268 104L248 122Z" fill="none" stroke="#43331f" stroke-width="1.3" stroke-linejoin="round"/>  <path d="M176 180L181 164L194 180M219 180L228 163L237 180M262 180L275 164L280 180M160 219L144 226L160 237M196 228L201 213L214 228M241 228L254 213L259 228M296 219L312 226L296 237M181 278L184 294L199 278M219 278L228 296L237 278M259 278L274 294L277 278" fill="none" stroke="#6f5a40" stroke-width="1" stroke-linejoin="round" stroke-linecap="round"/>  <path d="M300 300C316 312 326 330 328 350M286 318C302 330 312 346 314 362M268 332C282 344 290 356 292 368" fill="none" stroke="#a9906c" stroke-width="0.7"/>  <path d="M104 470C160 452 300 452 356 470C348 516 112 516 104 470Z" fill="none" stroke="#43331f" stroke-width="1.2" stroke-linejoin="round"/> <path d="M118 470C170 458 290 458 342 470" fill="none" stroke="#6f5a40" stroke-width="0.8"/> <path d="M104 470L118 470M130 456L134 466M180 452L182 462M228 451L228 461M276 452L274 462M326 456L322 466M356 470L342 470" fill="none" stroke="#a9906c" stroke-width="0.7"/> <path d="M120 500L112 516L128 506M160 510L152 524L170 514M204 514L198 528L214 518M248 514L242 528L258 518M292 510L286 524L302 514M330 500L324 516L340 506" fill="none" stroke="#43331f" stroke-width="1.1" stroke-linejoin="round"/>  <g fill="none" stroke="#6f5a40" stroke-width="1" stroke-linejoin="round"> <path d="M140 486C140 472 160 468 172 476C184 484 182 500 168 504C150 508 140 500 140 486Z"/> <path d="M204 490C204 474 226 470 240 478C252 486 250 504 234 508C214 512 204 504 204 490Z"/> <path d="M268 486C268 472 288 468 300 476C312 484 310 500 296 504C278 508 268 500 268 486Z"/> </g> <path d="M148 484C160 478 172 482 178 492M212 488C224 482 236 486 242 496M276 484C288 478 300 482 306 492" fill="none" stroke="#a9906c" stroke-width="0.7"/>  <path d="M156 490C150 490 148 498 154 502C160 506 168 502 166 494C164 489 160 489 156 490Z" fill="none" stroke="#6f5a40" stroke-width="0.9"/> <path d="M284 490C278 490 276 498 282 502C288 506 296 502 294 494C292 489 288 489 284 490Z" fill="none" stroke="#6f5a40" stroke-width="0.9"/> <path d="M220 492C213 492 211 501 218 505C225 509 233 504 231 496C229 490 224 490 220 492Z" fill="none" stroke="#b5502a" stroke-width="1.2"/>  <text x="228" y="540" text-anchor="middle" font-family="'Liberation Sans','DejaVu Sans',sans-serif" font-size="8" letter-spacing="2" fill="#6f5a40">CROSS-SECTION OF THE ARILS</text> <text x="230" y="590" text-anchor="middle" font-family="'Liberation Sans','DejaVu Sans',sans-serif" font-size="11" letter-spacing="1.5" fill="#43331f">DURIO ZIBETHINUS · KING OF FRUITS</text> </svg>

<figcaption><em>Plate 7. Durio zibethinus, the King of Fruits — the armoured husk, the five-celled cutaway and the custard arils, with the twin chemistry of ester and sulphur that composes its perfume.</em></figcaption> </figure>

The kitchen answer to all of this — the way a cook brings a bold food to a nervous guest — is rarely to serve it raw and alone. It is to set it in company, to let the transforming ingredient do its work as one voice in a dish rather than a solo. The durian goes into sticky rice with coconut and sugar; the surströmming into its flatbread; the nattō over hot rice with mustard and a raw egg. The century egg has the gentlest introduction of all, and it is the recipe this chapter offers, because it is genuinely easy, entirely safe, and served in exactly this form in homes and cold-dish shops across southern China and Taiwan.

Century-Egg Tofu — Pídàn Dòufu (皮蛋豆腐)

The kindest possible doorway to the century egg: cool silken tofu, halved pídàn, and a bright, savoury dressing — a five-minute cold dish eaten across southern China and Taiwan on hot days.

Serves 2 as a small dish · Time 10 minutes, no cooking

Ingredients

1 block (about 300 g / 10½ oz) chilled silken or soft tofu
2 century eggs (pídàn), shells removed
1 tbsp light soy sauce
1 tsp black rice vinegar (Chinkiang) — optional, for lift
1 tsp toasted sesame oil
1 tsp caster sugar, dissolved in the soy
1 spring onion, finely sliced
1 tbsp chopped coriander (optional)
a little chilli oil or a few sliced fresh chilli, to taste
toasted sesame seeds, to finish

Method

Turn the chilled tofu out onto a shallow serving plate, keeping the block whole, and cut it into thick slices or 2 cm (¾ in) cubes.
Peel the century eggs and rinse; cut each into quarters or sixths. A knife dipped in water, or a length of thread drawn through, gives clean segments without smearing the soft yolk. Arrange them over and around the tofu.
Stir the soy, dissolved sugar, vinegar and sesame oil together and spoon evenly over the top.
Scatter with spring onion, coriander, chilli and sesame seeds. Serve cold, at once, sharing straight from the plate.

Cook's note: Buy pídàn from a Chinese or Southeast Asian grocer or a reputable online seller, and choose the modern lead-free (wúqiān, 无铅) kind; commercially produced century eggs are cured to modern food-safety standards and are entirely safe eaten straight from the shell — no cooking required. Choose eggs that feel firm; a good one, cut open, shows the pale "pine-flower" crystals across its amber white. This is the authentic serving, and the tofu's coolness is not a disguise for the egg but a frame for it.

Every food in this chapter answers a local problem — a long winter, a summer glut, a rainforest that needed its seeds carried — and each was loved into a cuisine by the people who solved it. The nerve, where nerve was needed at all, was almost always the visitor's; the knowledge, and the safety that rides on it, always belonged to the people who made the food. There remains one whole class of prized food at which the Western table still balks harder than at any shark or egg or fruit, though some two billion people eat it daily and always have. It has six legs, and it is where this book goes next.

[^1]: The popular telling that hákarl is "buried" understates the craft and overstates the grave: traditional and modern makers ferment the shark in drained gravel pits or perforated boxes that let the fluids run off, and it is the long open-air drying that follows, not the burial, that does most of the work of carrying the amines away.

บทถัดไป · 7 / 15Chapter 4 — The Small & the Six-Legged