English: Seasoned cod roe / Deutsch: Eingelegter Kabeljaurogen / Español: Huevas de bacalao sazonadas / Português: Ovas de bacalhau temperadas / Français: Oeufs de morue assaisonnés / Italiano: Uova di merluzzo stagionate /
Mentaiko in Japanese and called Myeongranjeot in Korean refers to the marinated cod or pollock roe (eggs) which is used as a common ingredient in both Japanese and Korean Cuisines and is usually made from variety of flavors and colors.
It is usually eaten by itself or with Sake and Onigiri. Nowadays it becomes popular in other Asian countries like Thailand as a sauce for spaghetti mixed with butter or mayonnaise.
Karashi Mentaiko is a variety of Mentaiko which is spicy and is a product of Fukuoka City in Japan.
Other /More definition:
Mentaiko refers to Japanese spicy, marinated cod roe or very tiny fish eggs. It is one of the foods which Fukuoka is renowned for. There are many Japanese recipes which have use for mantaiko, in Fukuoka, Mentaiko Spaghetti is an example.