Citrus is a general term for orange, mandarin, orange, kumquat, pomelo, and medlar. The citrus trees are evergreen and have beautiful trees. The flowers are solitary or 2-3 clusters; the calyx is irregularly 5-3; the petals are usually less than 1.5 cm long; the stamens are 20-25, the styles are slender, and the stigma is head-shaped. Flowering period from April to May, fruiting period from October to December.

Citrus has the functions of nourishing blood and nourishing blood, enhancing memory, preventing cancer and cancer, appetizing and eliminating food, controlling appetite, ecchymosis, wrinkle removal, beauty, anti-aging and helping development.

Vitamin C contained in orange peel is much higher than pulp. Vitamin C is ascorbic acid, which plays an antioxidant role in the body, can lower cholesterol and prevent blood vessel rupture or oozing. Vitamin C and vitamin P can enhance scurvy Therapeutic effect; regular consumption of orange peel tea is beneficial for people with arteriosclerosis or vitamin C deficiency. People who are coughing and sipping cough should not eat citrus.