On storage
the integrity of albumin structure is lost; as a result albumin spreads thinly when
broken on a cooking surface. Egg weight, albumen and yolk height, Haugh unit,
albumen and yolk indices decreased with increase in storage time while albumen
and yolk width increased. Egg length and width were not affected by storage
time and method. The quality of egg albumin is measured by measuring Albumin
index, Haugh’s unit
H.U varies
with storage – 82 at farm; 77 for whole sale; 60 for retail. For an egg of poor
quality H.U ranges from 36-60 while for a egg of good quality HU is 72.
Instrument
required
- Tripod micrometer
- weighing balance
Procedure
- Take a sample (egg)
- egg is weighed
- after that egg is broken onto a flat surface (breakout method), and a micrometer used to determine the height of the thick albumen (egg white) that immediately surrounds the yolk.
- The height, correlated with the weight, determines the Haugh unit, or HU, rating.
The higher the number, the better
the quality of the egg (fresher, higher quality eggs have thicker whites).
Although the measurement determines the protein content and freshness of the
egg, it does not measure other important nutrient contents such as the micronutrient or vitamins present
in the egg.
Formula
The formula for calculating
the Haugh unit is:
Where:
·
HU = Haugh unit
·
h = observed height of the albumen in
millimeters
·
w = weight of egg in grams
- H.U is the function of height of thick albumin and weight of the egg. Measurement of height of thick albumin is done by using micrometer.
Haugh Unit rating
|
Quality of eggs
|
90 and above
|
Excellent
|
80 - 89
|
Very good
|
70 - 79
|
Acceptable
|
65 - 69
|
Fair
|
60 - 64
|
Consumer resistance point*
|
55 - 59
|
Poor
|
50 and below
|
Unacceptable
|
Calculation of Haugh’s unit of egg
Reviewed by jobalertonwhatsapp
on
08:41:00
Rating:
Reviewed by jobalertonwhatsapp
on
08:41:00
Rating:
No comments: