Yuzu is traditional citrus in Japan, which is familiar at Japanese through the ages. Yuzu Rocks is 100% made from Japanese yuzu, to make both yuzu juice and yuzu aroma oil. Per Yuzu Rock, it contains yuzu aroma oil of pericarp of one yuzu. Straight yuzu juice content is up to 15%, as many as 75ml, straight juice from 5 yuzu fruits. Mix with soda at 1:1, tonic water at 1:1.