Egg whites are also known as albumen, accounts for ~ 60% of an egg's liquid weight. Beaten egg whites are an important component of many baked goods, such as cakes, because they provide structure, volume and leavening. As an egg ages, the egg white loses carbon dioxide, causing the white to become more thin and transparent. This causes older eggs to "spread out" in a pan, rather than retaining their shape and height. Egg white is an excellent source of protein and also contains niacin and riboflavin.