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.

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. 

Gulas is a Spanish product that dates back to 1991, when a company called Angulas Aguinaga created it by using surimi (processed fish paste) as an imitation of angulas (baby eels). The product looks almost the same as angulas, but it doesn’t have little pinprick eyes and a thin mouth, it’s softer than angulas, and the flavor is vaguely fishy.

This imitation product is so popular that it can be found in almost every grocery shop in the country. Gulas was created because angulas baby eels became scarce and prices rose, due to overfishing and environmental degradation. Nowadays, gulas is usually fried with garlic, oil, and chili peppers or cayenne pepper. 

Lumpfish roe is one of the more available roe varieties, and it is usually reasonably priced. It is harvested from lumpfish (Cyclopterus lumpus), which is mostly found in the cold waters of the North Atlantic. The natural color of the roe can vary, though it is usually pale gray or dusty pink.

However, most producers opt for artificial coloring to attain appealing red or black hues. The beads are small, mildly-flavored, briny, and subtly sweet. Lumpfish roe is an excellent addition to appetizers, salads, soups, or seafood-based main dishes. 

Surimi, meaning ground meat in Japanese, is a Japanese fish product made by grinding the meat of gutted, filleted, and cleaned fish to a smooth paste, which is then treated with cryoprotectants before it is frozen. A staple of traditional Asian cuisine, this product is distinguished by an absence of scent and creamy white color, and it is commonly prepared with the flesh of fish such as Alaska pollock, threadfin bream, blue hake, blue whiting, jack mackerel, and sardine.

The fish paste used to be traditionally made by hand, but the method of freezing the paste has given rise to the industrialized version. Although Japan has been considered the leading country of surimi production worldwide, these days this versatile fish paste is widely produced in many other countries around the world, including Vietnam, Korea, Thailand, China, New Zealand, and the US.

Bottarga di tonno, or tuna fish roe, is a cured delicacy from the Italian region of Sardinia. Made with salted, pressed, and dried tuna fish roe, bottarga di tonno used to be considered a poor man’s food, but nowadays it is a luxurious treat, often referred to as the gold of Sardinia.

With its extraordinary, rich, salty flavor and beautiful colors ranging from deep red-amber to brilliant orange-yellow, bottarga di tonno is a great addition to a wide range of dishes, but it is also delicious enough to be enjoyed on its own, flavored with a touch of lemon juice and a drizzle of extra virgin olive oil.

Narutomaki or naruto is a traditional type of fish cake and a type of kamaboko (cured fish surimi) that’s most commonly used as ramen topping. It’s made by wrapping white fish paste (surimi) that’s been colored with red food dye around undyed fish paste.

The combination is rolled into a log, steamed until solid, then cut into thin slices. On the cross-section, there is a spiral after which it was named because it’s reminiscent of the famous Naruto whirlpools which appear between Shikoku and Awaji Island. 

Tobiko is a Japanese term for flying fish roe. The natural color of this roe is bright orange, but sometimes other ingredients, such as squid ink or yuzu, can be added to impart the roe with various colors and slightly alter its flavor.

Tobiko eggs are smaller than ikura (salmon roe), but they have a similar crunchy texture. Their flavor is often described as salty, smoky, and subtly sweet. Tobiko can be enjoyed on its own, but it is mostly used as an ingredient in gunkan sushi or as a garnish on various sushi rolls.

Bottarga di muggine or mullet roe is one of the most renowned Sardinian foods. To prepare this delicacy, roe pouches of Mugil Cephalus, or flathead grey mullet, are first cleaned, cured in sea salt, pressed, then dried.

The result is a delicacy with a salty flavor and a dense, silky texture. Bottarga can be shaved, sliced, chopped, or grated, and even a small amount can provide a lot of flavor to a wide range of dishes. Thinly sliced and flavored with lemon juice and olive oil, bottarga is often served as an appetizer, and when it's finely chopped, it makes a great addition to fresh vegetable salads.