This slides shows the Parts of an eggs and its function, egg history, egg structure and cooking method.

1. EGGS
Prepared by:
Daisy T. Bangayan
UNIVERSITYOFSAINTLOUIS- TUGUEGARAO

2. OBJECTIVES
• Define the meaning of egg.
• Discuss the history, uses, and cooking
issues of eggs
• Students will learn to identify the parts
and structure of the egg.
• Identify the composition of the eggs.
• Enumerate the egg size and egg grading.
• Value the importance of eggs.

3. What Is an Egg?
•Eggs are poultry products from
chicken, duck, and quail that eaten
as food.
•An egg is a reproductive cell from
which a new organism develops. This
will occur only if the egg has been
united with a male sperm cell
(fertilized).

5. History
•Bird eggs have been valuable
foodstuffs since prehistory, in
both hunting societies and more
recent cultures where birds were
domesticated.

6. • The chicken was probably domesticated
for its eggs from jungle fowl native to
tropical and subtropical Southeast Asia
and India before 7500 BCE. Chickens were
brought to Sumer and Egypt by 1500 BCE,
and arrived in Greece around 800 BCE,
where the quail had been the primary
source of eggs.

7. • In Thebes, Egypt, the tomb of
Haremhab, built about 1420
BCE, shows a depiction of a
man carrying bowls of ostrich
eggs and other large eggs,
presumably those of the
Pelican, as offerings.

8. •In ancient Rome, eggs were
preserved using a number of
methods, and meals often started
with an egg course.
• The Romans crushed the shells in
their plates to prevent evil spirits
from hiding there.

9. • In the Middle Ages, eggs were forbidden
during Lent because of their richness.
• The word mayonnaise possibly was
derived from moyeu, the medieval French
word for the yolk, meaning center or hub.
• Egg scrambled with acidic fruit juices
were popular in France in the 17th
century; this may have been the origin of
lemon curd.

10. • The dried egg industry developed in the 19th
century, before the rise of the frozen egg
industry.
• In 1878, a company in St. Louis, Missouri
started to transform egg yolk and white into a
light-brown, meal-like substance by using a
drying process.
• The production of dried eggs significantly
expanded during World War II, for use by the
United States Armed Forces and its allies.

11. •In 1911, the egg carton was invented
by Joseph Coyle in Smithers, British
Columbia, to solve a dispute about
broken eggs between a farmer in
Bulkley Valley and the owner of the
Aldermere Hotel.
•Early egg cartons were made of
paper.

12. Parts and Structure of an Egg

13. Parts and Structure of an Egg
1. Yolk
- This is the yellow or orange portion found in
the center of the egg.
- the yolk is encased in a colorless membrane
called the vitelline membrane
2. White
- this also called the albumen
- the yolk is suspended in it by two yolk cords or
chalazae ( Kah-lay-za)

14. Parts of an Egg
3. Shell membrane
- there are two membranes, the inner and outer which are
readily seen when peeling hard cooked eggs.
4. Shell
- this is made up mainly of calcium carbonate.

15. Parts of an Egg
• When the egg is freshly laid, the shell is
completely filled. The air cell is formed by
contraction of the contents during cooling and
by the loss of moisture. A high-quality egg has
only a small air cell.
• The yolk is well-centered in the albumen and is
surrounded by the vitelline membrane, which is
colorless. The germinal disc, where fertilization
takes place, is attached to the yolk.

16. Parts of an Egg
• On opposite sides of the yolk are two, twisted,
whitish cord-like objects known as chalazae.
Their function is to support the yolk in the center
of the albumen. Chalazae may vary in size and
density, but do not affect either cooking
performance or nutritional value.
• A large portion of the albumen is thick.
Surrounding the albumen are two shell
membranes and the shell itself. The shell
contains several thousand pores that permit the
egg to "breathe."

17. Size of an Eggs
•Jumbo - 30 ounces per dozen
•Extra Large - 27 ounces per dozen
•Large - 24 ounces per dozen
•Medium - 21 ounces per dozen
•Small - 18 ounces per dozen
•Pee Wee - 15 ounces per dozen

18. Egg Grading
1.AA – shell
∀-have whites that are
thick and firm; yolks
that are high, round,
and practically free from
defects; and clean,
unbroken shells. Grade
AA and Grade A eggs are
best for frying and
poaching, where
appearance is
important.

19. 2. A-shell-
∀eggs have characteristics
of Grade AA eggs except
the whites are
"reasonably" firm. This is
the quality most often
sold in stores.

20. ∀3. B-shell-clean to slightly stained, air
cell over 3/16" deep, white-weaker and watery.
• 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 they are usually used to make liquid, frozen,
and dried egg products, as well as other egg-containing
products.

22. Cooking Issues
•Egg white coagulates, or solidifies,
when it reaches temperatures
between 144 °F and 149 °F (62.2 °C-
65 °C).
•Egg yolk coagulates at slightly higher
temperatures, between 149 °F and
158 °F (65 °C-70 °C).

23. •If a boiled egg is overcooked, a
greenish ring sometimes appears
around egg yolk due to the iron
and sulfur compounds in the egg.
•It can also occur when there is an
abundance of iron in the cooking
water.

24. •The green ring does not affect the
egg's taste; overcooking, however,
harms the quality of the protein
• Chilling the egg for a few minutes in
cold water until it is completely
cooled prevents the greenish "ring”
from forming on the surface of the
yolk.

25. •Cooking also increases the risk
of atherosclerosis due to
increased oxidization of the
cholesterol contained in the
egg yolk.

26. Uses
•It is sometimes separated from
the egg whites and used in
cooking (for mayonnaise,
custard, hollandaise sauce,
and crème brûlée).

27. •It is used in painting as a
component of traditional egg-
tempera.
•It is used in the production of
egg-yolk agar plate medium,
useful in testing for the presence
of Clostridium perfringens.

28. • Egg yolks also contains an antibody called
antiglobulin. The antibody transfers from the
laying hen to the egg yolk by passive immunity
to protect both embryo and hatchling from
microorganism invasion.
• Egg yolk can be used to make liqueurs such as
Advocaat or eggnog.
• Egg yolks are used to extract Egg Oil which has
various cosmetic, nutritional and medicinal
uses.

29. Egg Cookery
•Egg cooked in the shell
•Hard-cooked Egg -
Eggs must not be boiled but
simmer for about 20 minutes
for a hard- cooked egg.

30. • The cooked egg should be immersed in cold
water and flushed in running water
immediately after cooking to avoid darkening
of the yolk.
• The greenish coloration of the yolk is due to the
formation of iron sulfide during cooking. Iron
comes from the yolk and the sulfide from the
white.

31. • Characteristics
•-Tender albumen not
rubbery
•-Yolk is well centered
•-No yolk darkening
•-Easy to peel

32. Rules to follow in the hard
cooking of eggs
• -Use fresh eggs
• -Allow to stand overnight at room temperature
• -Simmer for 20 minutes
• -Put the egg in when water is about to boil to
have less cracks.
• -Cool immediately in running water.

33. •Soft – cooked egg – has a tender
but firm albumen, yolk is slightly
thickened yet not firm at the
edges.
• A good soft cooked egg may be
obtained by simmering for 5
minutes with enough water to
cover the egg.

34. Eggs cooked out of the shell

35. •Poached eggs are those broken
out of the shell and dropped into
simmering water to coagulate.
•A drop of vinegar gives a smooth
textured product.

36. •Fried eggs are the most popular
breakfast preparation and sometimes
called eggs coked sunny side up.
• The eggs are broken out of the shell and
pan fried in small amount of oil without
breaking the yolk.
• The upper surface of the yolk is basted
with hot oil.
• Non- stick pan is recommended to use.

37. •Shirred eggs –
resembles fried eggs,
except that it starts on
top of the stove and
finished in the oven
individually.

38. • Scrambled eggs- are prepared by
whipping the whole egg out of the shell
and pan frying just like fried egg.
• Another way is to whip the white first
into stiff foam and add the yolk as
whipping is continued.
• Milk may be added to lower the
coagulation temperature and to affect a
softer product.

40. • Omelets are sophisticated scrambled
eggs. The first part of the technique is
similar for making scrambled eggs.
• The similarity ends there and the omelet
emerges from the pan not as shapeless
pile of curds on an attractive oval with
light delicate texture.
• Many variations can be done in the
preparations of omelets.

42. • Soufflés – a standard entrée soufflé
consists of three elements:
• -Base – usually heavy béchamel
• -Flavor ingredients – cheese, vegetables,
sea foods, meat
• -Egg whites – delicately beaten
• The ingredients are folded gently and
bake in a soufflé dish and served
immediately from the oven to the dining
table.
•

44. Unscramble the Scrambled Eggs
1. dirresh
3. lehls 4.geg
5. oymrbe 6. gingrad
7. iecckhn 9.orcuibtna
10. ingsw 11. Tapemertrue
12.llec 13.zalachae
2.olky
14. branemsem 15.izdeltirfe
SEAT WORK
8.
lesfofus

45. THANK YOU AND
HAVE A NICE DAY!