Surströmming is a fermented fish product made with strömming, a type of herring, sourced from the cold waters of the Baltic Sea, usually in spring. The fish is salted, cleaned, and allowed to ferment before being canned. This herring is defined by a rather distinctive and strong odor that results from its fermentation process, which is initiated by a type of lactic acid enzyme in the herring’s spine and it doesn’t cease even after the fish has been canned.

Despite its strong smell, the fermented herring has an interesting flavor that is a perfect mix of piquant, savory, and acidic. There’s also an annual surströmming festival (surströmmingsskiva) in Alfta, Halsingland, which traditionally takes place on the third Thursday in August, when a significant number of enthusiastic Swedes and fans of this fermented fish delicacy gather to savor the contents of numerous bulging cans of surströmming. 

Hákarl is Iceland's national delicacy made from cured shark flesh, namely Greenland shark and other sleeper sharks. The meat is first fermented for up to three months, then hung and left to dry for another four to five months. There are two varieties of the dish: the chewy, reddish glerhákarl, and tender, white skyrhákarl.

It is often considered to be food for the brave, because the high ammonia content often makes people gag. The cured shark meat is typically cut up into cubes and served on toothpicks with an accompanying shot of a local spirit known as brennivin.

Shirako is a Japanese specialty consisting of cod's milt, or sperm sacs. It is characterized by its unusual visual appearance and a creamy, buttery flavor. Traditionally, shirako is served either raw or slightly grilled, and it is recommended to consume it when it's as fresh as possible.

Shirako is often poached with ponzu sauce, or tempura-fried with yuzu kosho condiment on the side. The word shirako means white children, and the ingredient is in season during winter. Although shirako is an acquired taste, it is served in restaurants all over Japan.

Fesikh is a popular Egyptian dish consisting of dried, fermented, and salted gray mullet. The fish is dried in the sun by a specialist called a fasakhani. If prepared incorrectly, the dish can cause poisoning, so it is traditionally stored in firmly closed glass jars.

Fesikh is served during the Sham-El-Nessim festival, accompanied by finely chopped onions, lemon wedges, and Egyptian bread.

Karp zatorski is a fish hybrid of the Cyprinus carpio species, cultivated by cross-breeding the Karp Zatorski pure line with the Hungarian, Yugoslav, Golysz and Israeli pure lines of fish. The carp is raised in winter ponds feeding on natural food with the addition of cereals, in the Malopolskie Province in Poland.

The fish grow up to 2 kilograms in weight. Their unique features are a curved back, compact shape and an olive green to blue color. Due to their pond-raising, the meat doesn't have any hints of a muddy taste, but is instead delicately fresh and flavorful, with a lower fat content than in standardly marketed fish. 

Třeboňský kapr is a carp of the common carp species, reared in fish ponds in the Třeboň Basin, Třeboňsko Protected Landscape Area in the Czech Republic. The fish have a dark green, gray or gray-blue back and yellowish-white bellies.

Their bodies are characterized by a high back, and they grow to a size of up to one meter, with a weight of 20 kilograms. However, they are slaughtered when they are three or four years old when their weight ranges from 1,20 to 3,20 kilograms. The meat is of the highest quality and has quite a low content of fat. 

Kazunoko is a Japanese term for salted herring roe that is typically marinated in dashi stock. This yellow roe is slightly elongated and filled with tiny round eggs that pop and release their briny flavor when eaten. In Japan, herring roe is usually first desalted and then marinated in dashi stock, which is often seasoned with soy sauce, kelp (seaweed), and bonito flakes.

The word translates as number (kazu) and child (ko), and the dish symbolizes a prosperous future and fertility. Because of this, kazunoko is one of the essential courses served during Japanese New Year festivities—collectively called Osechi-ryōri. 

Fugu is the Japanese word for a fish known as pufferfish, blowfish, or globefish. The fish is infamous for its poisonous parts that contain the lethal poison tetrodotoxin, highly concentrated in the liver, ovaries, eyes, and skin. Trained chefs who want to prepare fugu must undergo scrutinized testing and licensing that is done at local government level.

However, some people prefer the light numbing sensation that the fugu toxin produces, so they ask the chefs to serve them small parts of the toxic organs. In Japan, fugu is usually consumed in specialized restaurants that serve a complete meal which typically includes several courses of the fish served in varying ways, such as fugu sashimi, boiled fugu chiri, fugu rice porridge, or deep-fried fugu. 

Geoduck is a large, unusually shaped clam that is native to the west coast of North America, namely Pacific Northwest and Western Canadian coast. It consists of a long soft body, often referred to as a neck or siphon, which hangs from the shell, and which may reach up to 3.3 feet (1 m).

With a small foot, these clams bury themselves in the ground, and they remain at the same place for the rest of their lives. As a culinary ingredient, geoduck is an expensive delicacy. It is usually just shortly boiled before it is eaten. The shell is removed, and the skin that covers the trunk is peeled off.