Usda egg dating
In 2009, an estimated 62.1 million metric tons of eggs were produced worldwide from a total laying flock of approximately 6.4 billion hens. As the size of the air cell increases and the quality of the egg decreases, the grade moves from AA to A to B.
Bird eggs have been valuable foodstuffs since prehistory, in both hunting societies and more recent cultures where birds were domesticated. This provides a way of testing the age of an egg: as the air cell increases in size due to air being drawn through pores in the shell as water is lost, the egg becomes less dense and the larger end of the egg will rise to increasingly shallower depths when the egg is placed in a bowl of water.
Egg whites may be aerated or whipped to a light, fluffy consistency, and often are used in desserts such as meringues and mousse.
Ground egg shells sometimes are used as a food additive to deliver calcium.
sometimes they are obtainable from farmers, poulterers, or luxury grocery stores. It forms around both fertilized and unfertilized yolks.
In many countries, wild bird eggs are protected by laws which prohibit the collecting or selling of them, or permit collection only during specific periods of the year. The primary natural purpose of egg white is to protect the yolk and provide additional nutrition during the growth of the embryo.
Whipping for meringue takes significantly longer, but the final volume is virtually the same.
If a boiled egg is overcooked, a greenish ring sometimes appears around egg yolk due to changes to the iron and sulfur compounds in the egg.
In 1911, the egg carton was invented by Joseph Coyle in Smithers, British Columbia, to solve a dispute about broken eggs between a farmer in Bulkley Valley and the owner of the Aldermere Hotel. The most commonly used bird eggs are those from the chicken, duck, and goose eggs. Although there is no significant link between shell color and nutritional value, often there is a cultural preference for one color over another (see 'Color of eggshell', below).
In addition, the protein in raw eggs is only 51 percent bioavailable, whereas that of a cooked egg is nearer 91 percent bio-available, meaning the protein of cooked eggs is nearly twice as absorbable as the protein from raw eggs.
As a cooking ingredient, egg yolks are an important emulsifier in the kitchen, and are also used as a thickener, as in custards.
Smaller eggs, such as quail eggs, are used occasionally as a gourmet ingredient in Western countries. Brown eggs have significantly higher incidence of blood spots due to candling being less effective.
Eggs are a common everyday food in many parts of Asia, such as China and Thailand, with Asian production providing 59 percent of the world total in 2013. "White" is the common name for the clear liquid (also called the albumen or the glair/glaire) contained within an egg. In chickens, it is formed from the layers of secretions of the anterior section of the hen oviduct during the passage of the egg. Cuticula The shape of an egg resembles a prolate spheroid with one end larger than the other and has cylindrical symmetry along the long axis. The larger end of the egg contains an air cell that forms when the contents of the egg cool down and contract after it is laid.