Eggs as food

People have eaten eggs for a long time.

Most eggs come from chickens. People also eat eggs from ducks.

Some eggs are very large. These come from ostriches.

An egg has a shell. Inside is a white part. The white part protects the yellow yolk.

Some eggs have two yolks. This happens when two yolks join.

Eggs can be many colors. They can be white or brown. Some are even blue-green.

Eggs are a great food for everyone.

People have eaten eggs for millions of years.

Most eggs we eat come from chickens. We also eat eggs from ducks and geese.

Some eggs are very small, like quail eggs. Other eggs are huge, like ostrich eggs.

In ancient Egypt, people gave eggs as offerings. In ancient Rome, people crushed shells to scare evil spirits.

An egg has several parts. The shell protects the inside. Under the shell is a clear film called a membrane.

Inside is the albumen, which is the egg white. The white part is mostly water. It protects the yolk. The yolk is the yellow center. Sometimes, an egg has two yolks. This happens if two yolks join together.

Egg colors can change. Most chicken eggs are white or brown. Some are even blue-green. The color of the yolk also changes. This depends on what the hen eats. If a hen eats plants with yellow pigments, the yolk looks bright.

Eggs are a very useful food. We use them in many dishes. You can eat them fried or scrambled.

Eggs are one of the most useful foods in the world.

People have eaten them for millions of years. Most people eat eggs from chickens, but we also eat eggs from ducks and geese.

Some eggs are very small, like quail eggs, which are used as special ingredients. Other eggs are huge, like those from ostriches. In some places, people even eat eggs from gulls or guineafowl. Eggs are so important that they are used in many parts of the food industry.

An egg has several interesting parts inside a shell.

First, there is a clear film called a membrane. Inside that is the albumen, which is the egg white. The white is mostly water and it protects the yolk. The yolk is the yellow center of the egg. Sometimes, an egg might have two yolks if they join together. The yolk's color depends on what the hen eats. If she eats plants with yellow pigments, the yolk looks very bright.

Humans have a very long history with eggs.

Ancient Egyptians showed people carrying ostrich eggs as offerings in tombs. In ancient Rome, people even crushed shells in their plates to stop evil spirits. During the Middle Ages, people did not eat eggs during Lent. This helped farmers let their flocks rest. In the 1600s, people in France mixed eggs with fruit juice to make lemon curd.

Today, making eggs is a huge global business.

In 2017, the world produced 80.1 million tonnes of chicken eggs. China is the largest producer with 31.3 million tonnes. The United States is also a big producer with 6.3 million tonnes. In 2009, there were about 6.4 billion hens in the world. These hens produced an estimated 62.1 million metric tons of eggs.

We can use eggs in many tasty ways.

You can eat them fried, like a sunny-side-up egg, or scrambled.

Eggs are also used in many baked goods. People use them to make both sweet and savory dishes. Because they are so versatile, they are a common food in many different cultures. Whether they are part of a big meal or a quick snack, eggs are a special part of how we eat.

Eggs are one of the most versatile and widely consumed foods on Earth.

While humans have eaten bird eggs for millions of years, the modern food industry relies heavily on the chicken. Most people eat eggs from fowl, such as chickens, ducks, and geese. However, many other types exist.

Some cultures enjoy quail eggs as gourmet ingredients, while ostrich eggs serve as a luxury food. In parts of England and Scandinavia, gull eggs are considered a delicacy. In some African markets, you might find guineafowl eggs in the spring. Even fish eggs are eaten, known as roe or caviar. This diversity makes eggs a vital part of global nutrition and commerce.

To understand an egg, one must look at its complex anatomy.

An egg consists of a protective eggshell, the albumen, and the vitellus. The vitellus is the technical name for the yolk. The albumen, or egg white, is about 90 percent water and 10 percent protein. Its natural purpose is to protect the yolk and provide nutrition for a growing embryo. The yolk is suspended in the white by spiral bands of tissue called chalazae. These structures help keep the yolk centered. The shell itself is made of various proteins and pigments. For example, brown shells get their color from protoporphyrin IX, while blue shells come from biliverdin.

The internal characteristics of an egg can change over time. A fresh egg has a small air cell at the larger end. This air cell forms when the contents cool and contract after being laid. As an egg ages, water is lost through the shell's pores, making the air cell larger. You can test an egg's age by placing it in a bowl of water. A very fresh egg will sink, but an old egg may float. Sometimes, eggs show unusual features. A double-yolk egg occurs when ovulation happens too quickly. A yolkless egg might appear when a young hen, called a pullet, first begins laying. There are even double-shelled eggs caused by specific muscle contractions in the oviduct.

Human history is deeply connected to the domestication of birds.

Scientists believe chickens were likely domesticated for their eggs before 7500 BCE. These birds descended from wild jungle fowl in Southeast Asia and the Indian subcontinent. By 1500 BCE, chickens had reached Egypt and Sumer. In ancient Egypt, the tomb of Haremhab shows people carrying ostrich and pelican eggs as offerings. In ancient Rome, eggs were so important they often started a meal course. Romans even crushed shells in their plates to ward off evil spirits. During the Middle Ages, eggs were forbidden during Lent. This was partly religious, but it also allowed farmers to let their flocks rest and save feed.

Egg production has become a massive global industry. In 2017, the world produced 80.1 million tonnes of chicken eggs. China is the largest producer, contributing 31.3 million tonnes. The United States follows with 6.3 million tonnes, and India produces 4.8 million tonnes. In 2009, there were approximately 6.4 billion hens in the world. These hens produced an estimated 62.1 million metric tons of eggs. This scale of production requires advanced technology, such as candling, to check egg quality.

Culinary uses for eggs are nearly endless. They are used in both sweet and savory dishes, including many baked goods. In the seventeenth century, French cooks scrambled eggs with acidic fruit juices. This practice may have created the origin of lemon curd. Today, you might eat them fried, like a sunny-side-up egg, or scrambled.

Beyond the kitchen, egg components have other uses. The proteins in egg whites are used in the preparation of vaccines, such as those for influenza. The membranes of the shell are even used commercially as dietary supplements.

The way we handle and package eggs has changed with technology and values. In 1911, Joseph Coyle invented the egg carton to prevent breakage. While polystyrene cartons became popular for their protection, the twenty-first century has seen a return to paper. This shift is due to environmental concerns and the use of biodegradable materials. Today, egg production faces debates regarding methods of mass production. For instance, the European Union banned battery husbandry for chickens in 2012. As the industry evolves, it continues to balance the massive global demand with new regulations and environmental needs.