In Australia, commercial farms normally use Hy-Line Brown, ISA Brown and Hi-Sex Brown breeds. These breeds also have brown feathers. America mostly uses Leghorn chickens. These hens have white feathers and white eggs!
The eggshell colour depends on the breed of the hen. Generally speaking, white shell eggs come from hens with white feathers, while brown shell eggs are produced by hens with brown feathers.
While it is true that eggs are cleaned before being packaged and sent to your grocery store, they are not bleached. In fact, most eggs start out white, but different breeds are genetically coded to release different colored pigments as the egg passes through the hen's oviduct. Voilà!
According to Michigan State University Extension, egg color is determined by the genetics of the hens. The breed of the hen will indicate what color eggs she will produce. For example, Leghorn chickens lay white eggs while Orpington's lay brown eggs and Ameraucana produce blue eggs.
The U.S. Department of Agriculture (USDA) determined that the best way to fight Salmonella contamination is by sanitizing the eggs before they reach the consumer. The washing process removes contaminants, but it also removes the natural coating of the egg, leaving the shell porous.
Egg yolks vary in colour from dark orange to almost white and this variation is almost entirely due to the pigments in the chicken's food. A diet rich in pigments will produce eggs with darker yolks.
The main egg colour available in Australia is brown, although a small number of farms also sell white eggs. While many people assume brown eggs are more natural and therefore healthier, that's not the case. Brown hens lay brown eggs, white hens lay white eggs, and they both have the same nutritional profile.
Why do we not get white eggs anymore? We are now seeing white eggs appear in our supermarkets more often. The reason we see fewer white eggs is due to the ratio of chicken in the UK. It is estimated that of the 40m egg-laying birds in the UK, only about 250,000-300,000 are breeds that lay white eggs.
White eggs in the United States are not bleached, contrary to popular internet belief. The color, instead, depends on the kind of chicken that is laying the egg, and it usually corresponds with the color of the chicken's earlobe.
Egg washing is not required in Australia, but sale of dirty eggs is prohibited by Food Standards Australia New Zealand (FSANZ). Storing washed eggs below 7°C can help reduce the ability of Salmonella to grow.
Commercially sold eggs in America go through a washing and sanitizing process that clears contaminants, but also removes the natural protections that eggs have against bacteria. Because of this, eggs are refrigerated during processing and must remain chilled in order to reduce the risk of salmonella contamination.
As you suspected, the reason Americans eggs tend to have bright yellow yolks has nothing to do with "hormones" but rather with what we feed our hens. Beyer says egg yolk color is almost entirely influenced by the birds' diet. So if you're feeding birds yellow corn, "it gets in the egg," he explains.
Australian egg yolks are artificially brightened with additive food dyes placed into the chook's feed pellets. IF you think a bright yellow or orange egg yolk is a sign of a healthy well-cared for chicken think again.
In the US, to reduce the risk of salmonella infection, eggs are washed and sprayed with a chemical sanitiser before they are sold to the public.
No. The color of the shell does not affect the nutrient content. There is no nutritional difference between a white and a brown egg. The breed of the hen determines the color of her eggs.
But why is this? About 40 years ago, people decided that they didn't like the look of white eggs, so brown eggs were the ones sent to supermarkets for selling, and white eggs were reserved for restaurants and cafes aka where customers wouldn't seem them in their shells.
According to French Wikipedia, French chickens used to lay mainly white eggs. But French chickens were cross-bred with Asian breeds starting in about 1850, and now all the eggs are brown (called œufs rosés in French).
Europeans take a different approach. In the United Kingdom, for example, producers instead vaccinate laying hens to prevent the transmission of salmonella. They then rely on a thin, naturally occurring coating called the cuticle, to prevent any contamination from the outside of the shell penetrating to the egg.
That's because five years ago the industry switched their breeder supply and stopped producing white eggs, due to a lack of demand. "New Zealanders love brown eggs," says Michael Brooks, executive director of Egg Producers Federation of New Zealand. "They love what they perceive as a natural feel about brown eggs.
The egg industry faces supply issues impacted by rising feed costs and a hangover from the pandemic restrictions which reduced laying flocks. Egg Farmers of Australia told SBS in 2022 the industry had been impacted by bushfires, floods, droughts, the mice plague, COVID-19 and increased production costs.
Pasture-Raised Eggs / Pastured Eggs): Pasture-raised eggs (sometimes referred to as pastured eggs) are the healthiest eggs to buy, no question. Pasture-raised means that the hens are free to roam and graze freely in a large open pasture.
The shade of an egg yolk is completely determined by the hen's diet. Hens who are given feed full of yellow-orange pigments will lay eggs with darker yolks. It's as simple as that! No artificial coloring is allowed in chicken feed, but some farmers will add marigold petals to give egg yolks an orangey color boost.
Hens that truly are pasture-raised, foraging on green plants and bugs, have a diet full of these carotenoids. As a result, their yolks have this bright orange color, so this color is a sign of a healthy diet full or nutrients.
But what about those yolks, folks? Research conducted by the United States Department of Agriculture has demonstrated that the color of the yolk also does not affect the egg's nutritive value. All yolks contain less water, more fat and a little less than half of the protein as the egg's white.