f. The size and movement of the air cell which are permitted in the various
qualities are as follows:
Quality
Depth
Movement
AA
Not over 1/8 inch
May show unlimited movement
and may be free or bubbly
A
Not over 3/16 inch
May show unlimited movement
and may be free or bubbly
B
Not over 3/8 inch
May show unlimited movement
and may be free or bubbly
B*
No limit
May show unlimited movement
and may be free or bubbly
3-14. AIR CELL GAUGE
a. The air cell gauge may be used by the beginner until he can learn to judge
the size of the air cell accurately at a quick glance while candling. More experienced
candlers occasionally use the gauge to check the accuracy of their determinations.
b. The depth of the air cell is measured at the point of greatest distance between
the top of the cell and an imaginary plane passing through the egg at the lower edge of
the air cell where it touches the shell (figure 3-4). Air cell movement is the distance the
air cell moves away from its normal position when the egg, with the air cell uppermost,
is twirled.
3-15. THE YOLK
a. General. The appearance of the yolk as the egg is twirled in candling is one
of the best indicators of the interior quality of shell eggs. The characteristics of the yolk
are determined by the shadow that it casts upon the shell before the candling light. The
appearance of the yolk is dependent on the condition of the albumen. However, there
are three factors about the yolk itself that are considered in judging egg quality by the
yolk. These are:
(1)
Distinctness of yolk shadow outline.
(2)
Size and shape of yolk.
(3)
Defects and germ development.
MD0713
3-14