The outer skin of Ginkgo biloba contains a large amount of hydrogenated gingko acid and ginkgo flavonoids. The odor is due to the presence of these two substances.

The fruit of the ginkgo tree is commonly known as ginkgo, so ginkgo is also called the ginkgo tree. The ginkgo tree grows slowly and has an extremely long life. Under natural conditions, it takes more than 20 years from planting to bearing ginkgo fruits, and it takes 40 years to produce a large number of ginkgo fruits. Therefore, some people call it the "Gongsun tree". The meaning of "Sun Deshi" is the old longevity star in the tree, which has ornamental, economic and medicinal value. No fruit is formed, and there is no peel on the outside of the seeds, but they are directly exposed to the air. The "fruit" of Ginkgo we call is actually the seeds of Ginkgo.

The seeds of Ginkgo biloba can be divided into two parts: seed coat and seed kernel. The seed coat is divided into three layers from the outside to the inside: the outermost layer is the yellow fleshy outer testa; the middle is the white hard mesotesta (white husk); the inside is a thin red inner testa, which is wrapped around the seed kernel. (Ginkgo) outside. Among these three layers of testa, the outer testa contains a variety of volatile substances, mainly two low-grade fatty acids, butyric acid and caproic acid, which is why bursts of odor occur.