Yuzu is a small citrus fruit with an uneven skin. It comes in hues of yellow and green, depending on the degree of ripeness. It is a relatively small fruit, with diameter ranging from 5.5 to 7.5 cm.
Yuzu originated from Central China and Tibet. It is a hardy plant that can withstand frost. It was introduced to Japan and Korea during Tang Dynasty. Not surprisingly, it is where yuzu is most widely cultivated and widely used now. Yuzu is known for its characteristic aroma. On winter solstice, the Japanese has a custom that dates back to the early 18th Century of bathing with whole yuzu fruits. The yuzu fruits in bath is believed to warm the body, calm the mind, and guard against cold.
If you are ever in Japan, it is very likely you will come across yuzu in the food you order. You may find slivers of yuzu peel in a bowl of hot udon or soba noodles, or chawanmushi (steamed savoury egg custard). The aromatic oil in yuzu peel adds another dimension to these dishes. The peel can also be made into yuzu hachimitsu (a syrup that dissolves in water to make tea). Whilst the juice of yuzu can turn into vinegar and ponzu. Ponzu is a condiment for tataki (lightly grilled meat or fish), nabemono (one pot dish, such as shabu-shabu) or sashimi.