The octopus and its cephalopod cousins were already in existence hundreds of millions of years ago, protected by a shell that they gradually lost over time. They have always survived by rapidly adapting themselves to the vagaries of the planet's evolution.

They have two ways to protect themselves. One is their ability to change color immediately to match their environment and therefore become invisible. The other is the ink that they spit when they have to flee an enemy.

The octopus has always fascinated humans. This mythical sea creature has been the subject of various beliefs and fantasies. Nevertheless, they are still used for food. In ancient times, we know that the octopus was widely consumed, with the Romans believing it to have aphrodisiac properties.

The large quantity of protein in octopus means that it is widely fished and consumed in many countries. Japan, Spain, and the countries of the north-west coast of Africa are among the largest consumers. In North America and Australia, however, it is mainly used as bait for fishing.

Fresh octopus must be slippery, almost slimy, with suckers that stick to the fingers, and very firm tips of tentacles that do not break.

They should smell of the sea, salty without any acidity. A tangy smell means that they have started to decompose.

Octopus is sold fresh near where it is caught, frozen (whole or cut into pieces) from Morocco, China, Thailand etc., canned (cooked or semi-cooked), and vacuum packed (cooked).

Freshly caught octopus must be thoroughly cleaned. This consists of turning its head inside out and extracting everything contained inside (keeping the ink). Then the beak is removed and the skin pulled off from the head and tentacles. It must be rinsed several times.

Octopus must be tenderized before being cooked. The traditional method is to beat it for long enough to break down its muscle fibers. The easiest solution is to freeze it for at least 6 hours, and then thaw it at room temperature (not in the microwave) on the same day it is due to be cooked.

The head is removed, and the tentacles are cut into pieces, unless they are small.

Octopus is boiled for at least 45 minutes.

It is then marinated for 48 hours in olive oil, which develops its fragrances and finishes the tenderizing process.

Octopus goes well in a salad, broiled, or cooked a la plancha, and cooked in various sauces.

In Japan, where it is very widely consumed, octopus is eaten as sushi, takoyaki, or akashiyaki (dumplings flavored with chili). In Spain, the Galician octopus is a typical dish of Galicia.

Fresh octopus is best cooked on the day of purchase. Otherwise, it can be stored for 1 or 2 days at 1–5 °C.

But it is better to freeze it immediately. This also has the advantage of tenderizing it.

Frozen octopus must be put straight into the freezer, without interruption of the cold chain.

Low in fat, octopus is rich in protein and B vitamins, especially vitamin B12. It also contains many minerals, and is particularly rich in iron and selenium.

Two species of octopus are eaten, the Elledone, which lives on sandy bottoms and has only one row of suckers on its tentacles, and the Octopus, which prefers rocky bottoms and has two rows of suckers. Each has two varieties.

. Curled octopus (Elledone cirrhosa)

It is an orange-red color with a white underside. It is between 1116 cm long. It lives in a depth of between 10–150 m (sometimes 800 m) in the Atlantic, the English Channel, the North Sea, and the western Mediterranean (where it is abundant). It has very tender flesh.

. Musky octopus (Elledone moschata)

Its mantle is marked with dark spots. It is 14 cm long and quite rare. It is found in the Mediterranean and on the west coast of Spain. Its flesh has a distinctive flavor.

. Common octopus (Octopus vulgaris)

The most common. It is between 1020 cm long and its weight varies between 13 kg. It lives in the Mediterranean, across the Atlantic and the Pacific. Its flesh is less tender than the curled octopus.

. White-spotted octopus (Octopus macropus)

It has longer arms and has white spots on its mantle. It can grow up to 14 cm in length. It is more frequently found in the Atlantic and the Pacific than in the Mediterranean, where it is quite rare.

In some countries, octopus fishing is regulated and prohibited during breeding seasons: spring and autumn.

The European Union has set the minimum legal catch weight in the Atlantic, the Channel, and the North Sea at 750 g. This is not applicable in the Mediterranean. However, wherever they come from, the sale of gutted octopus weighing less than 450 g is prohibited.