Bird's nest is the nest of a swallow. However, it is not the nest of ordinary swallows, but the nest of a special kind of swallows, the Golden Bird's Nest.

Main ingredients: Modern medical research has found that the main ingredients of bird's nest are: water-soluble proteins, carbohydrates; trace elements: calcium, phosphorus, iron, sodium, potassium, and amino acids that play an important role in promoting the vitality of the human body.

Expanded Information:

Bird's Nests are made by a species of finch called "swiftlet".

The bird's nest is a kind of bird called "swiftlet", which uses moss, seaweed and soft plants to make a nest by mixing their feathers and saliva, as a hiding place. The bird's nests are taken down, refined and selected to become valuable bird's nests. "Swiftlets make nests three times a year, and the first time the nests are thick and white. Because the swiftlets have a long time to recuperate after a long winter, they store enough nutrients in their bodies, and their saliva is of a better quality, so the nests are thicker and better shaped, and they become marigolds, so they are called marigolds, and they are the finest of all bird's nests.

There is a type of bird's nest called "Blood Swallow", which is built by a kind of "Brown-tailed Golden Swallow". This kind of swiftlet may drink water of different quality, or the feed it eats may contain minerals and other factors, which may cause the red color of its saliva, thus making the "Blood Swallow". Therefore, they build the "Blood Swallow" nest. There is another type of swiftlet called "White Swiftlet", which is mostly produced in Indonesia, and there is another type called "Hairy Swiftlet", which is mostly produced in Brunei and Polo Island. This kind of Hairy Swiftlet is thinner, darker in color, with more feathers and impurities, and is mainly made from the nests of a kind of Swiftlet called "Gray-waisted Golden Swiftlet", while others with too many impurities and feathers are collectively called Hairy Swiftlet.

Reference:

Bird's Nest_Baidu Encyclopedia