The Compendium of Materia Medica records that lemon has the functions of promoting body fluid, quenching thirst, and dispelling heat. Modern medicine believes that lemon can prevent cardiovascular disease; in addition, lemon also has a strong antioxidant effect, which is very effective in delaying aging and inhibiting pigmentation. It has therapeutic effects on bronchitis, rhinitis, and urinary infections. Citric acid in lemon is an important raw material for making lemon balm, moisturizer and shampoo; citric acid can also be made into lemon soda; in addition, it is also a cooking seasoning, rich in nutrition, has therapeutic value, and is mostly processed into beverages, fruit juice, Cake, jam, candied fruit, canned food, etc.