Food On A Plate Shouldn't Move : Krulwich Wonders... Why does this dead octopus dance on your dinner plate when you pour soy sauce on it? Grab your fork, some salt and a sturdy seat, and get ready for some post-mortem antics.

Food On A Plate Shouldn't Move

There should be a law that says food on a plate shouldn't move.

Especially when you're about to eat it.

But this food in the video below? It moves. Oh boy, does it move. And thereby hangs a tale.

(And before you watch, a warning: the squid you're about to see is dead. Completely, totally dead, like a steak...and yet...)


Let me say this one more time, the squid (head removed, tentacles left on) was killed, like a lobster, just before the meal was served. If you eat animals, this squid died the way cows, fish and birds die; to feed us. Nothing especially cruel in that. But being dead, how come it "danced" off the plate?

Blame the soy sauce.

Soy sauce, rich in salt, caused its muscle cells to fire. To get motion, add sauce.

Because this squid was just killed, its muscle cells were still intact and operational. A live squid moves it tentacles by sending an electrical command from its brain to its muscles. The commands say "contract" or "relax." But since this animal lost its head, its brain can't send signals. Salt acts as a substitute.

Extra sodium (the salt) sends ions to the cell that trigger the cell to open up, creating a cascade of chemical activities that causes the cell to fire, so the muscle twitches. That's why the camera person keeps pouring soy sauce on those tentacles.

You can do the same thing with frog legs (which totally amazed people 200 years ago.

Getting dead frog legs to dance was one of the 18th century's most talked about science experiments.) Here's a modern, salty version, and it's still pretty creepy.


The first time this was done, it was an accident. Luigi Galvani, a professor in Bologna, was playing around with electricity, not salt. He had placed a frog's leg on an electrically wired surface attached to two batteries and when he accidently touched an inner nerve with his scalpel, "its muscles not only contracted violently," says historian Patricia Fara, they also "kept time with sparks being discharged from the machine."

The frog looked frighteningly alive as long as the current flowed. Galvani was among the first to see that electricity can move through the moist, muscle tissue of the frog, but the frog was only an hors d'oeuvre. People have imaginations. People are ghouls.

Wikimedia Commons
A galvanised corpse.
Wikimedia Commons

Ten years later, (you know this is coming) someone tried this on a human. A dead one. Here's Professor Fara's description:

On a cold morning in January 1803, George Forster, a convicted murderer, was hanged at Newgate [in London]. After an hour, his body was taken down from the gallows and handed over to a visiting physics professor, who staged an imposing demonstration.

Watched by fascinated surgeons, the professor linked the prostrate corpse to a through battery with metal plates and wires. First he worked on Forster's face. When the current started to flow, the dead jaws quivered and one eye leered open. As the experiment proceeded, Forster's clenched fist rose into the air. Then his legs started to kick back violently and his back arched. Some bystanders thought that Forster was being restored to life.

Woah! This kind of thing attracts attention. All over Europe people wondered about the power of electricity to heal or give life to dead things. The poet Percy Shelly excitedly asked his friends what extraordinary effects might be achieved by a giant battery "of colossal magnitude, a well-arranged system of hundreds of metallic plates."

His wife, Mary Shelley, was wondering the same thing. And for sheer drama, her version, published in 1818, takes us from science straight to awe:

It was on a dreary night of November, that I beheld the accomplishment of my toils. With an anxiety that almost amounted to agony, I collected the instruments of life around me, that I might infuse a spark of being into the lifeless thing that lay at my the glimmer of the half-extinguished light, I saw the dull yellow eye of the creature open; it breathed hard, and a convulsive motion agitated its limbs.

Makes a single squid dancing on a bowl of rice seem almost boring, doesn't it?

Patricia Fara's account of early experiments with electricity is called An Entertainment for Angels: Electricity in the Enlightenment (Columbia University Press, 2002). The Mary Shelley quotation is from her novel, Frankenstein. The dish featured in the video is a mix of salmon, seaweed and caviar — topped off with squid. It's commonly served in Hakodate, a northern Japanese town (hit hard by the recent tsunami). The dancing presentation, is, according to Food Japan, a new marketing ploy introduced by a single, publicity savvy restaurant, Ikkatei Tabiji, in Hokodate. They charge 2,000 yen per serving. That's about $24.40. After the dance, the squid is removed, sliced and re-served. This dish has a name. It's called "Odori-Don," and the reviewer who went there said it had a "morbid suck the inside of your mouth." Yuck. Food Japan suggests that because cephalopods (including squid) have a well-distributed nervous system, their muscle cells might be more robust and twitch longer. I don't know.