1. Look: the bird's nest should be a filamentous structure, and the flaky structure is not a real bird's nest; Pure bird's nest is not completely transparent, but translucent, whether it is soaked or watched under the light. \x0d\2。 Smell: Bird's nest has a unique smell, but it has no strong smell. Those with special smell, fishy smell or greasy smell are fakes; \x0d\3。 Touch: Take a small piece of bird's nest and soak it in water. When it is soft, pull it with silk strips, which has poor elasticity. If it is pulled, it is a fake; Rubbing with your fingers is also a fake that can be rubbed into a paste without elasticity; Blood Swallow and Huang Yan Dou are soaked fakes. \x0d\4。 Burn: dry the bird's nest slices with fire. If it is a real bird's nest, there will never be a crackling spark. \x0d\● Identification method of bleached bird's nest: \x0d\ Soak the bleached bird's nest in water and take it out. After about half a minute, rub your thumb and forefinger a few times, and your fingers will stick to the smell of chemicals. Moreover, the bleached bird's nest will not rise much after stewing, which is easy to water and has no natural egg white flavor. \x0d\● Identification method of coated bird's nest \x0d\ Take out the coated bird's nest immediately after soaking in water. After about half a minute, rub your thumb and forefinger several times, and your fingers will feel sticky and sometimes smell chemicals. \x0d\● Identification method of dyed bird's nest \x0d\ The so-called dyed bird's nest is mostly dyed red or yellow with low-priced Bai Yan and sold as high-priced blood swallow or yellow swallow. This kind of fake blood swallow is difficult to distinguish from Huang Yan before wet water. But once soaked, you can recognize it. Because the pigment dissolves in water, the clear water is immediately dyed red or yellow. And after stewing for an hour or two, its texture is soft and rotten like Bai Yan, and red or yellow is completely ineffective in water. The real blood swallow and yellow swallow, because they are true colors, will not change color after soaking and stewing. At the same time, because the blood swallow is rich in nutrients and minerals, the true blood swallow is still cool and solid after a long period of stewing. \x0d\● Identification method of seaweed bird's nest \x0d\ is more common in the market of Yan cake or shredded tobacco. There are real ones, and there are artificial bird's nests made of 100% seaweed after bleaching, drying and boiling. The color is pure white, not very shiny, thick and hard, with the smell of seaweed. Natural bird's nest strips are transparent, slightly yellow, shiny and odorless.