Surströmming: The World's Smelliest Food, Explained

The tin hissed like a punctured tire the moment my host's can opener bit in, and everyone but me took a smart step backward. We were outdoors, a good twenty feet from the house, and the smell still arrived like a physical event.

That was my introduction to surströmming, Sweden's infamous fermented herring. It's routinely called the smelliest food in the world, and having now met it in person, I won't be filing an appeal.

What Surströmming Actually Is

Surströmming is Baltic herring — strömming in Swedish — caught in spring and fermented in a light salt brine for months. The name translates to "sour herring," which undersells the situation considerably.

Here's the detail that gets people: fermentation doesn't stop when the fish is canned. It keeps working inside the sealed tin, which is why the cans visibly bulge on the shelf.

In any other aisle, a bulging can means you demand a refund. With surströmming, it means everything is going exactly according to plan.

How Bad Is the Smell, Really?

Bad. Think rotten eggs, sharp vinegar, and something distinctly low-tide, arriving all at once and filling an outdoor space in seconds.

The taste, though, is milder than the smell — locals will tell you this roughly four seconds after you first inhale. It's intensely salty and tangy, closer to a very loud anchovy than to anything actually spoiled.

That gap between nose and tongue is the dish's whole secret. People who push past the opening blast often end up genuinely liking it.

Opening the Tin Is a Whole Procedure

Rule one is non-negotiable: the tin gets opened outdoors. Not near an open window, not in a "well-ventilated kitchen" — outside, and preferably downwind of the table.

Many Swedes go a step further and open the can inside a bucket of water. The contents sit under pressure, so puncturing the lid can spray brine, and the water catches both the spray and the worst of the first wave.

Some airlines have banned the tins outright, treating pressurized cans of fermenting fish as a hazard. Whatever you think of the dish, that's a remarkable line on a food's résumé.

How Swedes Actually Eat It

Nobody sits down to a bare plate of surströmming. It's eaten as a klämma — a hand-rolled wrap built on tunnbröd, the soft flatbread of northern Sweden.

The classic build is flatbread, slices of buttery almond potato, pieces of herring, diced raw onion, and a spoonful of sour cream. Rolled up, the fish becomes one loud voice in a surprisingly balanced choir.

Plenty of people rinse the fillets first, and some add Västerbotten cheese to the wrap. However you build it, the sides aren't garnish — they're load-bearing.

A Northern Tradition With a Set Date

Surströmming belongs to northern Sweden, and above all to the High Coast — Höga Kusten — where steep UNESCO-listed shoreline meets villages that have fermented herring for centuries. The little island of Ulvön is often called its capital.

Traditionally the season opens on the third Thursday of August, the surströmmingspremiär. Sales used to be legally held back until late summer, and though that rule is long gone, the premiere stuck as the starting gun.

So late August up north means long outdoor tables, cold drinks, and tins hissing open across whole villages. It overlaps with crayfish season too — I covered that gloriously messy tradition in my piece on the Swedish crayfish party.

Why Would Anyone Eat This?

Fermenting was preservation long before refrigeration, and salt was once expensive along the Baltic. Using less of it let the fish ferment instead of cure, and it kept protein edible through the long northern winter.

What began as thrift hardened into identity. For a lot of northerners, the first tin of the season tastes like home, the way a specific barbecue style does for some of us back in the States.

For the record, everyday Swedish eating is reassuringly smell-neutral. I broke down the normal repertoire in what Swedes actually eat, and none of it requires a bucket.

Should You Try It?

Yes — once, outdoors, with Swedes who know what they're doing. This isn't a dish to attempt alone with a tin you smuggled home in a suitcase.

Build the full klämma, keep something cold to drink within reach, and don't hover over the open can. My honest scorecard: the first bite is alarming, the second is interesting, and by the third I understood why the whole table was smiling.

If the invitation ever comes, say yes — and let somebody else open the tin.