In the world, sweet oranges take the lead among fruits in production capacity. They are supplied in many varieties. According to their types, sweet oranges are generally divided into 4 kinds: “Valencia Orange”, “Liou Cheng”, “Chin Cheng”, “Bloody Orange” (with red pulp), “Chi Cheng”, and “Sour taste-free Orange” .

The most popular kinds of oranges are “Valencia Oranges” and “Liou Cheng”, which are widely grown throughout Taiwan. “Liou Cheng” was imported early in 1930 from Kuangtung Province, Mainland China. As each of them has a sunken circle in it, they are also called “Yin-tzi Kan”. Today, “Yin-tzi Kan” trees become Taiwan’s economic fruit trees in winter. “Yin-tzi Kan” is characterized by sweet juicy pulp, which is an essential for manufacturing fruit juice.