Tobiko is the Japanese word for the flying fish roe. It is most widely known for its use in creating certain types of sushi.
The eggs are small, ranging from 0.5 mm - 0.8 mm. For comparison, tobiko is larger than masago, (capelin roe), but smaller than ikura, (salmon roe). Natural tobiko has a red-orange color, a mild smoky or salty taste, and a crunchy texture.
Sometimes tobiko is colored to change its appearance, other natural ingredients are used to accomplish the change, such as, squid ink to make it black, yuzu to make it pale orange (almost yellow), or even wasabi to make it green and spicy. Sometimes a serving of tobiko contains several pieces, each having a different color.
When prepared as sashimi it may be presented on avocado halves or wedges. Tobiko is used in the creation of many other Japanese dishes. Often, Tobiko is used as an ingredient in California rolls.
Frequently masago, capelin or smelt roe, is substituted for tobiko, due to its similar appearance and flavor. The tiny size of the individual eggs is apparent to the experienced diner, however.
The raw roe is very nutritious, due to its high vitamin content, high protein content, and large ratio of omega-3 to omega-6 fatty acids. Although it contains a large amount of cholesterol, the amount of roe consumed in typical servings, about a tablespoon, does not create an issue in a healthy diet since it amounts to approximately seventeen percent of the recommended daily value for cholesterol.
Sushi is commonly eaten with condiments. Sushi may be dipped in shoyu, soy sauce, and may be flavored with wasabi, a piquant paste made from the grated root of the Wasabia japonica plant.
True wasabi has anti-microbial properties and may reduce the risk of food poisoning. The traditional grating tool for wasabi is a sharkskin grater or samegawa oroshi. An imitation wasabi (seiyo-wasabi), made from horseradish, mustard powder and green dye is common. It is found at lower-end kaiten zushi restaurants, in bento box sushi and at most restaurants outside of Japan. If manufactured in Japan, it may be labelled "Japanese Horseradish".