Clarification
Eggs, especially whites, can clarify or clear various fluid products, including consommé, broth and even wine. When the fluid is heated, added egg white coagulates, capturing and holding minute particles.1 Depending on the size and weight of the encased particles, the cooked whites may sink to the bottom, allowing the clarified mixture to be carefully poured off. Sometimes the whites may bubble to the top where they are skimmed off, resulting in a crystal-clear product.2
References
https://winemakermag.com/26-a-clearer-understanding-of-fining-agents