A product used in mayonnaise, baked bread, cooked dishes, or even eaten alone (maybe with a little toast), the egg is a relatively inexpensive, extremely useful food. Bird eggs produced by chickens are the most commonly consumed egg and are quite nutritious, providing protein and other vitamins. When refrigerated, fresh eggs can be stored safely for 4-5 weeks, and storage within a carton will keep the eggs from absorbing other flavors and smells around them.
A hen will usually take 24-26 hours to produce an egg, and thirty minutes later she will start all over again. The egg produced will have a clear albumen (egg white) and a yellow colored yolk. Most often, eggs have only one yolk however, a hen can produce double yolked eggs, or an egg with no yolk at all. Eggs can range in color from white to brown to pink, or even speckled, but the shell color has nothing to do with the egg’s nutritional value. The color of the egg is more directly related to the color of the hen; hens with white earlobes and white feathers will lay white eggs, while hens with red earlobes and feathers will lay brown eggs. Eggs are graded into sizes: small, medium, large, extra-large, and jumbo. Most recipes call for the use of large eggs which are approximately 2 ounces.
Many commercial egg companies raise their hens in small cages crowded with other hens which restricts their natural behavior. Animal welfare advocates take issue with the conditions these hens are raised in as they are debeaked to prevent pecking of other hen’s eggs, and cannot build nests or dust bathe (normal chicken behavior). Many laying hens are slaughtered at one year of age because their production begins to decline. Some consumers choose to buy eggs produced by free range hens to support farmers who give the chickens outdoor access instead of keeping them in tight cages.
Chicken eggs, while inexpensive, provide very high quality protein and numerous vitamins and minerals. A single large chicken egg contains 7 grams of protein, and all of the egg’s vitamins are found in the egg yolk. Protein helps to stabilize glucose levels, builds lean muscle, and provides a feeling of satiety. Eggs are one of the few foods to naturally contain vitamin D, and also contain vitamins A and E. The yolk provides choline, a nutrient that is essential for proper brain development. Choline is especially important for pregnant and lactating women to ensure healthy brain development in a fetus or newborn baby.
Although the egg contains very important nutrients such as calcium, phosphorous, and potassium, it also contains about 300 mg of cholesterol, which is two-thirds the daily recommended amount, and about 10 grams of fat. Researchers are still debating over the health risks of eggs because although a large egg contains about 10 grams of fat, it is mostly unsaturated fat which is far less harmful than saturated fat. Also, one study showed that the human body did not absorb much of the cholesterol from eggs, and another study suggested that eggs lowered the bad LDL cholesterol in patients but raised the good HDL cholesterol levels.
Though egg shells act as a seal against the entrance of bacteria, broken eggs or those laid by unhealthy hens can present certain risks. One main egg related concern is salmonella. Experts advise to cook eggs thoroughly before eating because the heat will kill any harmful bacteria or other organisms present. Hens that are kept in very sanitary conditions have a very low incidence of salmonella, and on average, only one in 30,000 eggs produced will actually harbor the salmonella bacteria. Still, thoroughly cooking an egg will remove any possibility of ingesting harmful bacteria. Even healthy, cooked eggs can present a problem for certain individuals because eggs commonly provoke an allergic reaction, especially in children. Doctors actually recommend feeding only the yolk to children because many are allergic to the egg white. If exposure is kept low, many kids will grow out of the egg allergy.
While eggs are a great breakfast food, providing energy and protein to start the day, they are also found in yummy desserts like custard and meringue, used in protest (egging), and decorated as an Easter holiday tradition. Though egg consumption declined to a low in 1991 because of lifestyle changes, it is now increasing as more people become aware of the health benefits that eggs offer. Eggs are an important dietary staple throughout the world, especially in Japan, Canada, and Korea (leading egg importers), and a whole carton of eggs can still be purchased for approximately one dollar.