Accurate nutrient
composition is valuable
for the egg industry
Ever more eggs are being processed nowadays, rather than being sold fresh ‘in shell’.
A recent publication giving the analysis of a range of products will help to clarify
standards and aid processors to achieve the best margins.
What is a trans-fat?
According to the US Food and
Drug Administration (FDA),
‘Basically, trans-fat is made when
manufacturers add hydrogen to
vegetable oil – a process called
hydrogenation. Hydrogenation
increases the shelf-life and flavour
stability of foods containing these fats.
Trans-fat can be found in vegetable
shortenings, some margarines and
many types of processed foods.
Trans-fat, like saturated fat
and dietary cholesterol, raises the
low density lipoprotein (LDL)
cholesterol that increases the risk
for coronary heart disease.’
Because of the association
between trans-fat and coronary
heart disease, several countries,
including the USA, are making
their citizens aware of the trans-fat
content of foods by introducing
a labelling system. These systems
often highlight those products
– like eggs – that contain no or
negligible amounts of trans-fat.
Nutrient values of egg products
Protein (g)
Moisture (g)
Total lipid (g)
Ash (g)
Carbohydrate (g)
Energy (cal)
Cholesterol (mg)
Whole
eggs
12.0
75.2
9. 7
0.8
2. 2
144.0
400
Yolk
15. 3
56.8
23.0
1.4
3. 6
282
991
Values given per 100g product
Source: American Egg Board
In 2005, the American Egg
Board (AEB) funded an updated
analysis of egg products, which
it published under the title Egg
Products Reference Guide. I presented
the results of this study at this year’s
International Egg Commission
meeting in London.
Nine egg products were analysed
including liquid/frozen whole eggs,
liquid/frozen salted whole eggs,
liquid/frozen yolk, liquid frozen
sugared yolks, liquid/frozen salted
yolks, liquid/frozen whites, dried
whole eggs, dried yolks and dried
stabilised whites.
Samples analysed were collected
from major processors in different
parts of the USA. Each product
included samples from three different
processors. The samples included
three different lots, which were
pooled. Egg products were analysed
for proximate composition and
cholesterol (see table) as well as
vitamins, minerals, fatty acids and
amino acids. Egg chemistry data
including pH, fat, protein, ash, solids,
and free glucose were also presented.
Liquid/frozen
Sugared Salted Salted
yolk yolk whole eggs White
13. 9 14.1 11.0 9. 3
51.2 50.9 67.8 89.0
20. 8 20. 9 9. 2 0.076
1.1 10. 4 10. 3 0.4
13.0 3. 8 1.7 1.3
294 259 133 43
917 912 387 3. 3
Dr Glenn Froning
With respect to proximate analyses,
moisture and protein content was quite
comparable to previously reported
values. Total fat was determined rather
than total lipids. Total fat is defined as
the quantitated fatty acids expressed as
triglycerides. For labelling purposes,
the US Food and Drug Administration
requires reporting total fat. (Code of
Federal Regulations 101.9). Previous
analyses reported total lipids, which
includes phospholipids and cholesterol.
Thus, total fat of yolk, for example, will
be about 3% lower than total lipids
(AOAC acid hydrolysis method).
Cholesterol content
Cholesterol content of
whole egg and yolk was
similar to that reported
previously. In a recent
review of factors affecting
yolk cholesterol, it was
indicated that feeding
reductase inhibitors
(statins) to laying hens
could reduce as much as
46%. However, there were Dr Glenn
concerns with the effect Froning
Whole
eggs
48. 4
3. 7
39. 2
3. 4
5. 4
568
1630
Dried
Yolk
33. 7
2. 7
52.9
3. 3
7. 3
640
2307
Stabilised
white
84.6
6. 5
0.4
3. 6
4. 8
361
20
