Yuzu or Citrus junos is a citrus fruit and plant in the family Rutaceae.
The fruit looks somewhat like a small grapefruit with an uneven skin, and can be either yellow or green depending on the degree of ripeness.
Yuzu fruits (which are very aromatic) typically range between 5.5 cm and 7.5 cm in diameter, but can be as large as a regular grapefruit.
Yuzu closely resembles sudachi (a Japanese citrus from Tokushima) in many regards; they share a similar mandarin-ichang papeda ancestry, though yuzu eventually ripen to an orange colour, and there are subtle differences between the flavors of the fruit.
The yuzu's flavor is tart, closely resembling that of the grapefruit, with overtones of mandarin orange. It is rarely eaten as a fruit, though in the Japanese cuisine its aromatic zest (outer rind) is used to garnish some dishes, and its juice is commonly used as a seasoning, somewhat as lemon is used in other cuisines.
It is an integral ingredient (along with sudachi, daidai, and other similar fruits) in the citrus-based sauce ponzu, and yuzu vinegar is also produced.
Yuzu is often combined with honey to make yuzu hachimitsu a kind of syrup that is used to make yuzu tea or as an ingredient in alcoholic drinks such as the yuzu sour.
It is also used to make liquor and wine.