Eggs come in a variety of shapes and sizes from different birds like chickens, ducks, and emus. They have an internal structure including a yolk surrounded by albumen and held within a hard shell. The freshness of an egg can be tested by seeing if it sinks or floats in water, with very fresh eggs lying on their side at the bottom while older eggs will stand up or float. Eggs are best stored in their carton in the refrigerator and kept away from strong smells. When whipping egg whites, temperature, cleanliness, and absence of yolk are important for producing foam, and adding sugar or salt can impact the stability and volume of the foam produced.

1. 1
Eggs
What came first?
The chicken or the
egg?

2. 2
Origin of Eggs
 First fleet – variety of eggs
 Eaten long before
 Birds
– Chickens
– Quails
– Emu
– Duck

3. 3
Physical Properties
‘Ovoid’ in shape
Yolk
Albumen - egg whites
Chalazae - Is located in the albumen
Vitelline membrane - Surrounds the yolk.
Shell. Shell Membrane
Air Cell
Eggs Structure Handout

4. 4
Internal Structure

5. 5
Fresh Eggs
Float or sink?
As the egg ages carbon dioxide and
moisture passes out of the egg and is
replaced with air. This air allows the egg
to float. It should not be used.
A very fresh egg lies on its side at the
bottom of the water.
A fresh egg stands up in the water.

6. 6
Storage
Stored point down in fridge.
Stored away from smell substance
because shell is porus and will absorb
odours.
Carton important because moisture is
absorbed.

7. 7
Foaming Whites
What is egg foam?
Important aspects of foaming eggs
Cool temperature
Have no traces of yolk
Use clean dry utensils
What will happen if we
add salt or sugar
Lets find out…

8. 8
Foaming Whites
Experiment
 What are the difference of the foam when
the following is added:
Salt
Sugar
Nothing
Complete the table

9. 9
Applications of eggs
Coating
Binding
Glaze
Thicken
Garnish
Emulsify

10. 10
Nutritional Value
Protein
Also have fat soluble vitamin A D and E
Water soluble B complex vitamins
Mineral such as
Calcium
Phosphorus
Potassium
Magnesium
Iron.
It is interest to note that 75% of an egg is Water

11. 11
Our results
Experiment Results
Check out our foam
Which one worked best?
Why?

12. 12
Conclusion
So what was first?
The chicken or the egg?
Perraton et al, 2000; Major & Reily, 2000; Farm Pride, 1998).