Eggs characteristics

Shape The shape of an egg is an oval with one end larger than the other end. The egg has cylindrical symmetry along the long axis. The larger end contains the air cell that forms when the contents of the egg cool and contract after it is laid.

Shell The colour of an eggshell depends upon the breed of hen. Hens with white ear lobes lay white eggs. Hens with red ear lobes lay brown eggs. Although there is no significant link between shell colour and nutritional value, there is often a cultural preference for one colour over another. For example, in most regions of the United States, eggs are generally white; while in the northeast of that country and in the United Kingdom, eggs are generally light-brown.

Yolk The yolk in a newly laid egg is round and firm. As the yolk ages it absorbs water from the albumen which increases its size and causes it to stretch and weaken the vitelline membrane. The resulting effect is a flattened and enlarged yolk shape.

Yolk colour depends on the diet of the hen; if the diet contains yellow/orange plant pigments, then they are deposited in the yolk, colouring it. A colourless diet can produce an almost colourless yolk. Farmers may enhance yolk colour with artificial pigments, but in most locations this activity is forbidden.

White The colour of the egg white depends upon the presence of carbon dioxide. A fresh egg has a great deal of carbon dioxide, since it has not had time to escape, and the white looks very cloudy.

Size Chicken eggs are graded by size, for the purpose of sales. Raw eggs are classed according to size, as shown below:

X - very large, 73g and over

L - large, between 63g and 73g

M - medium, between 53g and 63g

S - small, below 53g

Culture Egg games have their origin in many cultures. A popular Easter tradition in some parts of the world is the decoration of hard-boiled eggs. Adults often hide the eggs for children to find, an activity known as an Easter egg hunt. Egg tapping is done by tapping one egg against another. The egg that survives the longest wins. An egg toss is a picnic game. Egg rolling dates back to the 1600’s. Eggs are blown, pushed with the nose, or rolled down a hill.

10.Answer the questions.

1.What shape does an egg have?

2.What does the larger end contain?

3.What does the colour of eggshell depend upon?

4.Is there a link between shell colour and nutritional value?

5.What is the yolk like?

6.What does the yolk colour depend on?

7.Why does the white of a fresh egg look cloudy?

8.In what ways are eggs used in culture?

11.Match the words with their definitions.

1. shell 2. yolk 3. white 4. chalaza

a) one of a pair of spiral threads of albumen holding the yolk of a bird's egg in position; b) the substance in an animal ovum consisting of protein and fat that nourishes the developing embryo; c) the viscous fluid that surrounds the yolk of a bird's egg; d) the protective calcareous or membranous outer layer of an egg.

12.What is described by the following adjectives? (See Text “Eggs Characteristics”)

oval large

round white

cloudy light-brown

firm

13.Describe the structure of an egg using the picture.

14.Study the following table and explain what the firmness of the yolk depends on.

Soft-cooked yolk A soft-cooked egg has a firm white and runny yolk.

Medium-cooked yolk A medium-cooked egg has a firm white and a slightly firm yolk.

Hard-cooked yolk A hard-cooked egg has both a firm white and yolk.

Egg Size	Degree of Doneness	Time Required
Medium	Soft-cooked yolk	3 minutes
	Medium-cooked yolk	5 minutes
	Hard-cooked yolk	10 to 12 minutes
Large	Soft-cooked yolk	4 to 5 minutes
	Medium-cooked yolk	6 minutes
	Hard-cooked yolk	12 to 15 minutes
Extra Large	Soft-cooked yolk	5 minutes
	Medium-cooked yolk	7 to 8 minutes
	Hard-cooked yolk	18 minutes

15.Read some interesting facts concerning eggs. Which of them are new for you?