Egg Cookery 10

How can you tell the
difference between a good
egg and a bad egg?
Grading

If you have chickens and plan on
selling eggs, grading and sizing is
required. As a general rule, you
should grade all your eggs before
you store, sell or consume them.
Grading

When grading eggs, both the
interior and exterior quality is
measured.
Grading

Two general components of
Egg quality:
-shell quality (exterior)
-Interior quality
Interior quality

Direct bearing on the functional
properties of egg.
Exterior Quality

Direct influence on microbial quality
Egg Grading

A form of quality control use to classify
eggs for exterior and interior quality.
Egg Grading: How?

 Exterior Grading:
- clean
- Shell should be rough and dull (fresh)
-oval
- one end wider than the other

 Eggs with cracked or broken shells should be
discarded.
 If you are selling the eggs, remove any with unusual
shapes, textures or thin spots on the shell. While they
are edible, they break easily and will be unacceptable
because of their appearance.

 Interior Grading:
-Grading the interior of the egg is performed by
a method called candling.
-Using an egg candler will allow you to examine
the air cell, the egg white (called albumen) and the yolk.
-Candling also lets you check for spots and
cracks.
Interior Grading includes:

 Air Cell- As the egg ages, the air cell depth grows
and the quality of the egg diminishes.
Interior Grading includes:

 White or Albumen - The quality is based on its
clarity and thickness.
-Look for a clear color without discolorations or
floating foreign matter.
-Thick albumen allows limited movement of the
yolk and indicates a higher quality egg.
Interior Grading includes:

 Yolk - The quality of the yolk is determined by the
distinctness of its outline and other features like size,
shape and absence of any blemishes or blood spots.
It should be surrounded by a dense layer of
albumen.
Interior Grading includes:

 Spots- - Candling can help reveal foreign matter like
blood spots or meat spots. Eggs with interior spots
should not be sold.
AA
Factor
A Quality
Quality
B Quality

Inedible
Air Cell
1/8 inch or
less in depth
3/16 inch or less
More than 3/16 inch
in depth
White
Clear, Firm
Clean, May be
Clean, May be weak and
Doesn't apply
reasonably firm watery
Yolk
Outline
slightly
defined
Outline may be
fairly welldefined
Outline clearly visible
Doesn't apply
None
Blood or meat spots
aggregating not more
than 1/8" in diameter
Blood or meat
spots aggregating
more than 1/8" in
diameter
Spots
(blood or None
meat)
Doesn't apply
Egg Cookery 10
Factors That influence Sizes of Eggs

 Breed
 Age of hen
 Weight
 Environmental Factors
(Native chickens have much smaller eggs than
commercial chickens)
(better fed chicken has much larger eggs.)
(heat, stress and overcrowding can lead to small eggs)