corn and
marigold
Marigold may refer to:
* Marigold (color), a yellow-orange color
It may also refer to:
Plants
* In the genus ''Calendula'':
** Common marigold, '' Calendula officinalis'' (also called pot marigold, ruddles, or Scotch marigold)
* In the genus ' ...
petals.
[Shell eggs from farm to table](_blank)
. USDA Food Safety and Inspection Service, (2011). In the US, the use of artificial color additives is forbidden.
Abnormalities
Abnormalities that have been found in eggs purchased for human consumption include:
*
Double-yolk eggs, when an egg contains two or more yolks, occurs when ovulation occurs too rapidly, or when one yolk becomes joined with another yolk.
*
Yolkless eggs, which contain whites but no yolk, usually occurs during a pullet's first effort, produced before her laying mechanism is fully ready.
* Double-shelled eggs, where an egg may have two or more outer shells, is caused by a counter-peristalsis contraction and occurs when a second oocyte is released by the ovary before the first egg has completely traveled through the oviduct and been laid.
* Shell-less or thin-shelled eggs may be caused by
egg drop syndrome.
Culinary properties
Types of dishes
Chicken eggs are widely used in many types of dishes, both sweet and savory, including many
baked goods. Some of the most common preparation methods include
scrambled,
fried,
poached,
hard-boiled, soft-boiled,
omelettes, and
pickled. They also may be eaten raw, although this is not recommended for people who may be especially susceptible to
salmonellosis, such as the elderly, the infirm, or pregnant women. In addition, the protein in raw eggs is only 51 percent
bioavailable, whereas that of a cooked egg is nearer 91 percent bioavailable, 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.
The
albumen (egg white) contains protein, but little or no
fat, and may be used in cooking separately from the yolk. The proteins in egg white allow it to form foams and aerated dishes. Egg whites may be aerated or whipped to a light, fluffy consistency, and often are used in desserts such as
meringues and
mousse.
Ground eggshells sometimes are used as a
food additive to deliver
calcium
Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar t ...
. Every part of an egg is edible, although the eggshell is generally discarded. Some recipes call for immature or unlaid eggs, which are harvested after the hen is slaughtered or cooked, while still inside the chicken.
Cooking
Eggs contain multiple proteins that gel at different temperatures within the yolk and the white, and the temperature determines the gelling time. Egg yolk becomes a
gel, or solidifies, between . Egg white gels at different temperatures: . The white contains exterior albumen which sets at the highest temperature. In practice, in many cooking processes the white gels first because it is exposed to higher temperatures for longer.
Salmonella is killed instantly at , but also is killed from , if held at that temperature for sufficiently long time periods. To avoid the issue of salmonella,
eggs may be pasteurized in-shell at for an hour and 15 minutes. Although the white then is slightly milkier, the eggs may be used in normal ways. 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
Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in ...
and
sulfur
Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formul ...
compounds in the egg. It also may occur with an abundance of iron in the cooking water. Overcooking harms the quality of the protein. Chilling an overcooked egg for a few minutes in cold water until it is completely cooled may prevent the greenish ring from forming on the surface of the yolk.
Peeling a cooked egg is easiest when the egg was put into boiling water as opposed to slowly heating the egg from a start in cold water.
Flavor variations
Although the age of the egg and the conditions of its storage have a greater influence, the bird's diet affects the flavor of the egg.
For example, when a brown-egg chicken breed eats
rapeseed (canola) or soy meals, its intestinal microbes metabolize them into fishy-smelling
triethylamine, which ends up in the egg.
The unpredictable diet of free-range hens will produce likewise, unpredictable egg flavors.
Duck eggs tend to have a flavor distinct from, but still resembling, chicken eggs.
Eggs may be soaked in mixtures to absorb flavor.
Tea eggs, a common snack sold from street-side carts in China, are steeped in a brew from a mixture of various spices, soy sauce, and black tea leaves to give flavor.
Storage
Careful storage of edible eggs is extremely important, as an improperly handled egg may contain elevated levels of ''
Salmonella''
bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were am ...
that may cause severe
food poisoning. In the US, eggs are washed. This cleans the shell, but erodes its
cuticle.
The USDA thus recommends refrigerating eggs to prevent the growth of ''Salmonella''.
Refrigeration also preserves the taste and texture, however, intact eggs (unwashed and unbroken) may be left unrefrigerated for several months without spoiling. In Europe, eggs are not usually washed, and the shells are dirtier, however the cuticle is undamaged, and they do not require refrigeration.
[ In the UK in particular, hens are immunized against salmonella and generally, their eggs are safe for 21 days.][
]
Preservation
The simplest method to preserve an egg is to treat it with salt
Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quanti ...
. Salt draws water out of bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were am ...
and molds, which prevents their growth. The Chinese salted duck egg is made by immersing duck eggs in brine
Brine is a high-concentration Solution (chemistry), solution of salt (NaCl) in water (H2O). In diverse contexts, ''brine'' may refer to the salt solutions ranging from about 3.5% (a typical concentration of seawater, on the lower end of that of ...
, or coating them individually with a paste of salt and mud or clay
Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4).
Clays develop plasticity when wet, due to a molecular film of water surrounding the clay part ...
. The eggs stop absorbing salt after approximately a month, having reached osmotic equilibrium
Osmotic pressure is the minimum pressure which needs to be applied to a solution to prevent the inward flow of its pure solvent across a semipermeable membrane.
It is also defined as the measure of the tendency of a solution to take in a pure s ...
. Their yolks take on an orange-red color and solidify, but the white remains somewhat liquid. These often are boiled before consumption and are served with rice congee.
Another method is to make pickled eggs, by boiling them first and immersing them in a mixture of vinegar
Vinegar is an aqueous solution of acetic acid and trace compounds that may include flavorings. Vinegar typically contains 5–8% acetic acid by volume. Usually, the acetic acid is produced by a double fermentation, converting simple sugars to ...
, salt, and spices, such as ginger or allspice. Frequently, beetroot juice is added to impart a red color to the eggs.[ If the eggs are immersed in it for a few hours, the distinct red, white, and yellow colors may be seen when the eggs are sliced.][ If marinated for several days or more, the red color will reach the yolk.] If the eggs are marinated in the mixture for several weeks or more, the vinegar will dissolve much of the shell's calcium carbonate and penetrate the egg, making it acidic enough to inhibit the growth of bacteria and molds. Pickled eggs made this way generally keep for a year or more without refrigeration.
A century egg or hundred-year-old egg is preserved by coating an egg in a mixture of clay
Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4).
Clays develop plasticity when wet, due to a molecular film of water surrounding the clay part ...
, wood ash, salt, lime, and rice straw for several weeks to several months, depending on the method of processing. After the process is completed, the yolk becomes a dark green, cream-like substance with a strong odor of sulfur and ammonia, while the white becomes a dark brown, transparent jelly with a comparatively mild, distinct flavor. The transforming agent in a century egg is its alkaline material, which gradually raises the pH of the egg from approximately 9 to 12 or more. This chemical process breaks down some of the complex, flavorless proteins and fats of the yolk into simpler, flavorful ones, which in some way may be thought of as an "inorganic" version of fermentation.
Nutrition
Egg sizes
Nutritional value
A medium/large chicken egg provides approximately 70 kilocalories (290 kJ) of food energy and 6 grams of protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respon ...
.["Full Report (All Nutrients): 01129, Egg, whole, cooked, hard-boiled"]
USDA Branded Food Products Database["Full Report (All Nutrients): 45174951, EGGS"]
USDA Branded Food Products Database
Eggs (boiled) supply several vitamins and minerals as significant amounts of the Daily Value (DV), including (per 100g) vitamin A
Vitamin A is a fat-soluble vitamin and an essential nutrient for humans. It is a group of organic compounds that includes retinol, retinal (also known as retinaldehyde), retinoic acid, and several provitamin A carotenoids (most notably ...
(19 percent DV), riboflavin (42 percent DV), pantothenic acid (28 percent DV), vitamin B12 (46 percent DV), choline (60 percent DV), phosphorus (25 percent DV), zinc
Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic t ...
(11 percent DV) and vitamin D (15 percent DV).
The diet of laying hens also may affect the nutritional quality of eggs. For instance, chicken eggs that are especially high in omega-3 fatty acid
In chemistry, particularly in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated or unsaturated. Most naturally occurring fatty acids have an unbranched chain of an even number of carbon atoms, ...
s are produced by feeding hens a diet containing polyunsaturated fats from sources such as fish oil, chia seeds
Chia seeds are the edible seeds of ''Salvia hispanica'', a flowering plant in the mint family (Lamiaceae) native to central and southern Mexico, or of the related ''Salvia columbariae'' of the southwestern United States and Mexico. Chia seeds a ...
, or flaxseeds
Flax, also known as common flax or linseed, is a flowering plant, ''Linum usitatissimum'', in the family Linaceae. It is cultivated as a food and fiber crop in regions of the world with temperate climates. Textiles made from flax are known in W ...
. Pasture-raised free-range hens, which forage for their own food, also produce eggs that are relatively enriched in omega-3 fatty acids when compared to those of cage-raised chickens.
A 2010 USDA study determined there were no significant differences of macronutrients in various chicken eggs.
Cooked eggs are easier to digest than raw eggs, as well as having a lower risk of salmonellosis.
Health effects
Cholesterol and fat
More than half the calories found in eggs come from the fat in the yolk; 50 grams of chicken egg (the contents of an egg just large enough to be classified as "large" in the US, but "medium" in Europe) contains approximately five grams of fat. Saturated fat (palmitic
Palmitic acid (hexadecanoic acid in IUPAC nomenclature) is a fatty acid with a 16-carbon chain. It is the most common saturated fatty acid found in animals, plants and microorganisms.Gunstone, F. D., John L. Harwood, and Albert J. Dijkstra. The Li ...
, stearic, and myristic acids) makes up 27 percent of the fat in egg. The egg white consists primarily of water (around 90 percent) and protein (around 10 percent) and contains no cholesterol and little, if any, fat.
There is debate over whether egg yolk presents a health risk. Some research suggests dietary cholesterol increases the ratio of total to HDL cholesterol and, therefore, adversely affects the body's cholesterol profile; whereas other studies show that moderate consumption of eggs, up to one a day, does not appear to increase heart disease risk in healthy individuals. Harold McGee argues that the cholesterol in the egg yolk is not what causes a problem, because fat (particularly saturated fat) is much more likely to raise cholesterol levels than the consumption of cholesterol.
Type 2 diabetes
Studies have shown conflicting results about a possible connection between egg consumption and type 2 diabetes
Type 2 diabetes, formerly known as adult-onset diabetes, is a form of diabetes mellitus that is characterized by high blood sugar, insulin resistance, and relative lack of insulin. Common symptoms include increased thirst, frequent urinati ...
.
A meta-analysis from 2013 found that eating four eggs per week was associated with a 29 percent increase in the relative risk of developing diabetes. Another meta-analysis from 2013 also supported the idea that egg consumption may lead to an increased incidence of type two diabetes. A 2016 meta-analysis suggested that association of egg consumption with increased risk of incident type 2 diabetes may be restricted to cohort studies from the United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...
.
A 2020 meta-analysis found that there was no overall association between moderate egg consumption and risk of type 2 diabetes and that the risk found in US studies was not found in European or Asian studies.
Cancer
A 2015 meta-analysis found an association between higher egg consumption (5 a week) with increased risk of breast cancer
Breast cancer is cancer that develops from breast tissue. Signs of breast cancer may include a lump in the breast, a change in breast shape, dimpling of the skin, milk rejection, fluid coming from the nipple, a newly inverted nipple, or ...
compared to no egg consumption. Another meta-analysis found that egg consumption may increase ovarian cancer
Ovarian cancer is a cancerous tumor of an ovary. It may originate from the ovary itself or more commonly from communicating nearby structures such as fallopian tubes or the inner lining of the abdomen. The ovary is made up of three different ...
risk.
A 2019 meta-analysis found an association between high egg consumption and risk of upper aero-digestive tract cancers in hospital-based case-control studies.
A 2021 review did not find a significant association between egg consumption and breast cancer. A 2021 umbrella review found that egg consumption significantly increases the risk of ovarian cancer.
Cardiovascular health
One systematic review and meta-analysis of egg consumption found that higher consumption of eggs (more than 1 egg/day) was associated with a significant reduction in risk of coronary artery disease. Another systematic review and meta-analysis of Dietary Cholesterol and Egg Consumption found that egg consumption was associated with an increased all-cause mortality and CVD mortality. These contrary results may be due to somewhat different methods of study selection and the use primarily of observational studies, where confounding
In statistics, a confounder (also confounding variable, confounding factor, extraneous determinant or lurking variable) is a variable that influences both the dependent variable and independent variable, causing a spurious association. Con ...
factors are not controlled.
A 2018 meta-analysis of randomized clinical trials found that consumption of eggs increases total cholesterol (TC), LDL-C and HDL-C compared to no egg-consumption but not to low-egg control diets. In 2020, two meta-analyses found that moderate egg consumption (up to one egg a day) is not associated with an increased cardiovascular disease risk. A 2020 umbrella review concluded that increased egg consumption is not associated with cardiovascular disease risk in the general population. Another umbrella review found no association between egg consumption and cardiovascular disorders.
A 2013 meta-analysis found no association between egg consumption and heart disease or stroke. A 2013 systematic review and meta-analysis found no association between egg consumption and cardiovascular disease or cardiovascular disease mortality, but did find egg consumption of more than once daily increased cardiovascular disease risk 1.69-fold in those with type 2 diabetes mellitus when compared to type 2 diabetics who ate less than one egg per week. Another 2013 meta-analysis found that eating four eggs per week increased the risk of cardiovascular disease by six percent.
Eggs are one of the largest sources of phosphatidylcholine ( lecithin) in the human diet. A study published in the scientific journal, ''Nature
Nature, in the broadest sense, is the physical world or universe. "Nature" can refer to the phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. Although humans ar ...
'', showed that dietary phosphatidylcholine is digested by bacteria in the gut and eventually converted into the compound TMAO, a compound linked with increased heart disease. Another study found that type 2 diabetes mellitus and kidney disease also increase TMAO levels and that evidence for a link between TMAO and cardiovascular diseases may be due to confounding
In statistics, a confounder (also confounding variable, confounding factor, extraneous determinant or lurking variable) is a variable that influences both the dependent variable and independent variable, causing a spurious association. Con ...
or reverse causality.
Other
Egg consumption does not increase hypertension risk. A 2016 meta-analysis found that consumption of up to one egg a day may contribute to a decreased risk of total stroke. Two recent meta-analyses found no association between egg intake and risk of stroke.
A 2019 meta-analysis revealed that egg consumption has no significant effect on serum biomarkers of inflammation
Inflammation (from la, wikt:en:inflammatio#Latin, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or Irritation, irritants, and is a protective response involving im ...
. A 2021 review of clinical trials found that egg consumption has beneficial effects on macular pigment optical density and serum lutein.
Contamination
A health issue associated with eggs is contamination by pathogenic bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were am ...
, such as '' Salmonella enteritidis''. Contamination of eggs with other members of the genus ''Salmonella'' while exiting a female bird via the cloaca may occur, so care must be taken to prevent the egg shell from becoming contaminated with fecal matter. In commercial practice in the US, eggs are quickly washed with a sanitizing solution within minutes of being laid. The risk of infection from raw or undercooked eggs is dependent in part upon the sanitary conditions under which the hens are kept.
Health experts advise people to refrigerate washed eggs, use them within two weeks, cook them thoroughly, and never consume raw eggs.[Eggs – No Yolking Matter]
." ''Nutrition Action Health Letter,'' July/August 1997. As with meat, containers and surfaces that have been used to process raw eggs should not come in contact with ready-to-eat food.
A study by the U.S. Department of Agriculture in 2002 (Risk Analysis April 2002 22(2):203-18) suggests the problem is not so prevalent in the U.S. as once thought. It showed that of the 69 billion eggs produced annually, only 2.3 million are contaminated with ''Salmonella''—equivalent to just one in every 30,000 eggs—thus showing ''Salmonella'' infection is quite rarely induced by eggs. This has not been the case in other countries, however, where ''Salmonella enteritidis'' and '' Salmonella typhimurium'' infections due to egg consumption are major concerns.
Egg shells act as hermetic seals that guard against bacteria entering, but this seal can be broken through improper handling or if laid by unhealthy chickens. Most forms of contamination enter through such weaknesses in the shell. In the UK, the British Egg Industry Council awards the lions stamp to eggs that, among other things, come from hens that have been vaccinated against '' Salmonella''.
In 2017, authorities blocked millions of eggs from sale in the Netherlands, Belgium, and Germany because of contamination with the insecticide fipronil
Fipronil is a broad-spectrum insecticide that belongs to the phenylpyrazole chemical family. Fipronil disrupts the insect central nervous system by blocking the ligand-gated ion channel of the GABAA receptor and glutamate-gated chloride (GluCl ...
.
Food allergy
One of the most common food allergies
A food allergy is an abnormal immune response to food. The symptoms of the allergic reaction may range from mild to severe. They may include itchiness, swelling of the tongue, vomiting, diarrhea, hives, trouble breathing, or low blood pressu ...
in infants is eggs.[Egg Allergy Brochure](_blank)
, distributed by Royal Prince Alfred Hospital Infants usually have the opportunity to grow out of this allergy during childhood, if exposure is minimized. Allergic reactions against egg white are more common than reactions against egg yolks. In addition to true allergic reactions, some people experience a food intolerance to egg whites. Food labeling practices in most developed countries now include eggs, egg products, and the processing of foods on equipment that also process foods containing eggs in a special allergen alert section of the ingredients on the labels.
Farming
Most commercially farmed chicken eggs intended for human consumption are unfertilized, since the laying hens are kept without roosters. Fertile eggs may be eaten, with little nutritional difference when compared to the unfertilized. Fertile eggs will not contain a developed embryo
An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sperm ...
, as refrigeration temperatures inhibit cellular growth for an extended period of time. Sometimes an embryo is allowed to develop, but eaten before hatching as with balut.
Grading by quality and size
The U.S. Department of Agriculture grades eggs by the interior quality of the egg (see Haugh unit The Haugh unit is a measure of egg protein quality based on the height of its egg white (albumen). The test was introduced by Raymond Haugh in 1937 and is an important industry measure of egg quality next to other measures such as shell thickness an ...
) and the appearance and condition of the egg shell. Eggs of any quality grade may differ in weight (size).
*U.S. Grade AA
**Eggs have whites that are thick and firm; have yolks that are high, round, and practically free from defects; and have clean, unbroken shells.
**Grade AA and Grade A eggs are best for frying and poaching, where appearance is important.
*U.S. Grade A
**Eggs have characteristics of Grade AA eggs except the whites are "reasonably" firm.
**This is the quality most often sold in stores.
*U.S. Grade B
**Eggs have whites that may be thinner and yolks that may be wider and flatter than eggs of higher grades. The shells must be unbroken, but may show slight stains.
**This quality is seldom found in retail stores because usually they are used to make liquid, frozen, and dried egg products, as well as other egg-containing products.
In Australia and the European Union
The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe. The union has a total area of and an estimated total population of about 447million. The EU has often been ...
, eggs are graded by the hen raising method, free range, battery caged, etc.
Chicken eggs are graded by size for the purpose of sales. Some maxi eggs may have double-yolks and some farms separate out double-yolk eggs for special sale.
File:Egg and maxi egg 1.jpg,
File:Egg and maxi egg 2.jpg,
File:Egg with two yellows.jpg,
Color of eggshell
Although eggshell color is a largely cosmetic issue, with no effect on egg quality or taste, it is a major issue in production due to regional and national preferences for specific colors, and the results of such preferences on demand. For example, in most regions of the United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...
, chicken eggs generally are white. However, brown eggs are more common in some parts of the Northeastern United States, particularly New England
New England is a region comprising six states in the Northeastern United States: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont. It is bordered by the state of New York to the west and by the Canadian province ...
, where a television jingle for years proclaimed "brown eggs are local eggs, and local eggs are fresh!". Local chicken breeds, including the Rhode Island Red, lay brown eggs. Brown eggs are preferred in China, Costa Rica, Ireland
Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...
, France
France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan ar ...
, and the United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...
. In Brazil
Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...
and Poland
Poland, officially the Republic of Poland, , is a country in Central Europe. Poland is divided into Voivodeships of Poland, sixteen voivodeships and is the fifth most populous member state of the European Union (EU), with over 38 mill ...
, white chicken eggs are generally regarded as industrial, and brown or reddish ones are preferred. Small farms and smallholdings, particularly in economically advanced nations, may sell eggs of widely varying colors and sizes, with combinations of white, brown, speckled (red), green, and blue (as laid by certain breeds, including araucanas, heritage skyline, and cream leg bar) eggs in the same box or carton, while the supermarkets at the same time sell mostly eggs from the larger producers, of the color preferred in that nation or region.
These cultural trends have been observed for many years. ''The New York Times'' reported during the Second World War that housewives in Boston preferred brown eggs and those in New York preferred white eggs. In February 1976, the '' New Scientist'' magazine, in discussing issues of chicken egg color, stated "Housewives are particularly fussy about the colour of their eggs, preferring even to pay more for brown eggs although white eggs are just as good". As a result of these trends, brown eggs are usually more expensive to purchase in regions where white eggs are considered "normal", due to lower production. In France and the United Kingdom, it is very difficult to buy white eggs, with most supermarkets supplying only the more popular brown eggs. By direct contrast, in Egypt
Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Med ...
it is very hard to source brown eggs, as demand is almost entirely for white ones, with the country's largest supplier describing white eggs as "table eggs" and packaging brown eggs for export.
Research conducted by a French institute in the 1970s demonstrated blue chicken eggs from the Chilean araucana fowl may be stronger and more resilient to breakage.[
Research at Nihon University, Japan in 1990 revealed a number of different issues were important to Japanese housewives when deciding which eggs to buy and that color was a distinct factor, with most Japanese housewives preferring the white color.
Egg producers carefully consider cultural issues, as well as commercial ones, when selecting the breed or breeds of chickens used for production, as egg color varies between breeds. Among producers and breeders, brown eggs often are referred to as "tinted", while the speckled eggs preferred by some consumers often are referred to as being "red" in color.
]
Living conditions of birds
Commercial factory farming
Intensive animal farming or industrial livestock production, also known by its opponents as factory farming and macro-farms, is a type of intensive agriculture, specifically an approach to animal husbandry designed to maximize production, whil ...
operations often involve raising the hens in small, crowded cages, preventing the chickens from engaging in natural behaviors, such as wing-flapping, dust-bathing, scratching, pecking, perching, and nest-building. Such restrictions may lead to pacing and escape behavior
Escape response, escape reaction, or escape behavior is a mechanism by which animals avoid potential predation. It consists of a rapid sequence of movements, or lack of movement, that position the animal in such a way that allows it to hide, freeze ...
.
Many hens confined to battery cages, and some raised in cage-free conditions, are debeaked to prevent them from harming each other and engaging in cannibalism. According to critics of the practice, this can cause hens severe pain to the point where some may refuse to eat and starve to death. Some hens may be forced to molt to increase egg quality and production level after the molting. Molting can be induced by extended food withdrawal, water withdrawal, or controlled lighting programs.
Laying hens often are slaughtered when reaching 100 to 130 weeks of age, when their egg productivity starts to decline. Due to modern selective breeding, laying hen strains differ from meat production strains. As male birds of the laying strain do not lay eggs and are not suitable for meat production, they generally are killed soon after they hatch.
Free-range eggs are considered by some advocates to be an acceptable substitute to factory-farmed eggs. Free-range laying hens are given outdoor access instead of being contained in crowded cages. Questions regarding the living conditions of free-range hens have been raised in the United States of America, as there is no legal definition or regulations for eggs labeled as free-range in that country.
In the United States, increased public concern for animal welfare
Animal welfare is the well-being of non-human animals. Formal standards of animal welfare vary between contexts, but are debated mostly by animal welfare groups, legislators, and academics. Animal welfare science uses measures such as longevit ...
has pushed various egg producers to promote eggs under a variety of standards. The most widespread standard in use is determined by United Egg Producers through their voluntary program of certification. The United Egg Producers program includes guidelines regarding housing, food, water, air, living space, beak trimming, molting, handling, and transportation, however, opponents such as The Humane Society have alleged UEP certification is misleading and allows a significant amount of unchecked animal cruelty. Other standards include "Cage Free", "Natural", "Certified Humane", and " Certified Organic". Of these standards, "Certified Humane", which carries requirements for stocking density and cage-free keeping and so on, and "Certified Organic", which requires hens to have outdoor access and to be fed only organic vegetarian feed and so on, are the most stringent.
Effective 1 January 2012, the European Union
The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe. The union has a total area of and an estimated total population of about 447million. The EU has often been ...
banned conventional battery cages for egg-laying hens, as outlined in EU Directive 1999/74/EC. The EU permits the use of "enriched" furnished cages that must meet certain space and amenity requirements. Egg producers in many member states have objected to the new quality standards while in some countries, even furnished cages and family cages are subject to be banned as well. The production standard of the eggs is visible on a mandatory egg marking
Egg marking is a form of egg labelling that includes an ''egg code'' stamped on the egg itself. In the EU there is a producer code regulated by law since 2004. It allows consumers to distinguish free range eggs and organic farming eggs from the i ...
categorization where the EU egg code begins with 3 for caged chicken to 1 for free-range eggs and 0 for organic egg production.
Killing of male chicks
In battery cage and free-range egg production, unwanted male chicks are killed at birth during the process of securing a further generation of egg-laying hens. In Germany in June 2019, a court decided that culling chicks "violates the country's laws against killing animals without a justifiable reason". However, the court permitted an exemption for hatcheries until a viable alternative is possible.
Cultural significance
A popular Easter
Easter,Traditional names for the feast in English are "Easter Day", as in the '' Book of Common Prayer''; "Easter Sunday", used by James Ussher''The Whole Works of the Most Rev. James Ussher, Volume 4'') and Samuel Pepys''The Diary of Samuel ...
tradition in some parts of the world is a decoration of hard-boiled eggs (usually by dyeing, but often by spray-painting). A similar tradition of egg painting exists in areas of the world influenced by the culture of Persia
Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkme ...
. Before the spring equinox
A solar equinox is a moment in time when the Sun crosses the Earth's equator, which is to say, appears zenith, directly above the equator, rather than north or south of the equator. On the day of the equinox, the Sun appears to rise "due east" ...
in the Persian New Year tradition (called '' Norouz''), each family member decorates a hard-boiled egg and they set them together in a bowl.
In Northern Europe and North America, Easter eggs may be hidden by adults for children to find in an Easter egg hunt. They may be rolled in some traditions.
In Eastern and Central Europe, and parts of England, Easter eggs may be tapped against each other to see whose egg breaks first.
Since the sixteenth century, the tradition of a dancing egg is held during the feast of Corpus Christi in Barcelona and other Catalan
Catalan may refer to:
Catalonia
From, or related to Catalonia:
* Catalan language, a Romance language
* Catalans, an ethnic group formed by the people from, or with origins in, Northern or southern Catalonia
Places
* 13178 Catalan, asteroid ...
cities. It consists of a hollow eggshell, positioned over the water jet from a fountain, which causes the eggshell to revolve without falling.
See also
* Fish eggs
* Cock egg
* Ham and eggs
* List of foods
References
External links
British Egg Industry and the Lion Mark
* ttps://www.fda.gov/food/guidanceregulation/guidancedocumentsregulatoryinformation/eggs/default.htm Egg InformationU.S. Food and Drug Administration (2011)
Egg Basics for the Consumer: Packaging, Storage, and Nutritional Information
. (2007) University of California Agriculture and Natural Resources. Accessed 23 May 2014.
{{DEFAULTSORT:Egg (Food)
Egg (food)
Types of food
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