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VETERINARY INSPECTION OF FRESH EGGS, EGG PRODUCTS
AND HONEY
EGGS
REGULATION (EC) No 853/2004 OF THE EUROPEAN
PARLAIMENT AND OF THE COUNCIL of 29 April 2004
Laying down specific hygiene rules for food of animal origin
TERMS
Food of animal origin means food of animal origin, including honey
and blood, live bivalve molluscs, live echinoderms, live tunicates, and
live marine gastropods intended for human consumption, and other
animals destined to be prepared with a view to being supplied live to
the final consumer.
Eggs means egg in shell (other than broken, incubated or cooked
eggs) that are produced by farmed birds and are fit for direct human
consumption or for the preparation of egg products.
Liquid egg means unprocessed egg contents after removal of the
shell.
Cracked eggs means eggs with damaged shell and intact
membranes.
Packing centre means an establishment where eggs are graded by
quality and weight.
Egg products means processed products resulting from the
processing of eggs, or various components or mixture of eggs, or
from the further processing of such processed products.
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EGGS
1. At the producer’s premises, and until sale to the consumer,
eggs must be kept clean, dry, free of extraneous odour,
effectively protected from shocks and out of direct sunshine.
2. Eggs must be stored and transported at a temperature,
preferably constant, that is best suited to assure optimal
conservation of their hygiene properties.
3. Eggs must be delieverd to the consumer within a maximum
time limit of 21 days of laying.
EGG PRODUCTS
I.
REQUIREMENTS FOR ESTABLISHMENTS
Food business operators must ensure that establishments for the
manufacture of egg products are constructed, laid out and
equipped so as to ensure separation of the following operations:
1. washing, drying and disinfecting dirty eggs, where carried out
2. breaking eggs, collecting their contents and removing parts of
shells and membranes, and
3. operations other than those referred to in points 1 and 2.
II.
RAW MATERIALS FOR THE MANUFACTURE OF EGG
PRODUCTS
Food business operators must ensure that raw materials used to
manufacture egg products comply with the following requirements.
1. The shells of eggs used in the manufacture of egg products
must be fully developed and contain no breaks.
However, cracked eggs may be used for the manufacture of
egg products if the establishment of production or a packing
centre delivers them directly to a processing establishment,
where they must be broken as soon as possible.
2. Liquid egg obtained in an establishment approved for that
purpose may be used as raw material. Liquid egg must be
obtained in accordance with the requirements of points 1,2,3,4
and 7 of Part III.
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COMMISSION REGULATION (EC) No 2073/2005
Of 15 November 2005
On microbiological criteria for foodstuffs
1.14. Egg products, salmonella, excluding products where the
manufacturing process or the composition of products will eliminate
the salmonella risk.
n = 5, c = 0, m and M: absence in 25 g (for products placed to the
market during their shelf-life)
1.15. Ready-to-eat foods containing raw egg, salmonella, excluding
products where the manufacturing process or the composition of the
product will eliminate the salmonella risk.
N = 5, c = 0, m and M: absence in 25 g or ml (for products placed to
the market during their shelf-life)
2.3.1. Egg products, enterobacteriaceae
N = 5, c = 2, m = 10 cfu/g or ml, M = 100 cfu/g or ml, the criterion
applied at the end of the manufactureing process, In case of
unsatisfactory result, checks on the efficiency of the heat treatment
and prevention of recontamination.
This is coupled with the program on the control of salmonella:
REGULATION (EC) No 2160/2003 OF THE EUROPEAN
PARLAIMENT AND OF THE COUNCIL of 17 November 2003, on
the control of salmonella and other specified food-borne agents
All salmonella serotypes with public health significance in laying hens
of rearing flocks (sampling in day-old chicks and pullets 2 weeks
before moving to laying phase or laying unit) and laying flocks
(sampling at every 15 weeks during the laying phase), at stage of
primary production.
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EGG IN GENERAL
Formation-developing of egg
The yolk of the egg is the matured ovum that is formed in the left
ovary of the poultry. When the ovum reaches the appropriate size, it
is released from the follicle and is fallen into the funnel shaped
diverticulum of the oviduct. The ovulation is 30-60 minutes after the
laying of the previous one. The ovum is surrounded by the vitelline
membrane.
The ovum advances rotating in the lumen of oviduct. While
advancing, from the secretum of closely located glands, the inner
tenuous, the middle dense and the outer tenuous albumen layers
and the chalaza that are between the middle layer and inner shell
membrane are formed. In the isthmus and in the next part of oviduct,
the double shell membrane and the calcareous shell are formed,
respectively. The latter will be covered by the cuticle just before
laying. The double shell membrane is separated at the blunted end of
the egg after laying).
Physico-chemical properties of egg
The chemical composition of egg
Water
Egg protein
Fat
Carbohydrate
Ash
Whole egg
73. 6
12.8
11.8
1.0
0.8
Albumen
87.9
10.6
0.9
0.6
Yolk of egg
48. 7
16.6
32.6
1.0
1.0
The yolk contains significant quantities of vitamin A, pigment
(carotinoids) and lecithin (12%).
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UGF-s (unidentified growth factors) (Zoo-animals)
The egg contains a significant quantity of enzymes (trypsine,
erepsine, lipase). Their quantity however, is increased significantly at
the beginning of development of the embryo. Special importance has
the lisosyme located in the albumen layer. It inhibits the
development of bacteria that penetrate through the pores into the
egg. The inhibitory action of lisosyme is inactivated by the yolk (in
eggs, in which the yolk and albumen is mixed together, bacteria can
proliferate well).
Albumen layers of egg precipitate at 57-60 C while the yolk at 6570 C. The pH of albumen layers of fresh egg is 7.6. Releasing the
high carbon dioxide content in contact with air, the pH of egg is
elevated up to 9.4-9.6. Thus, this is not the result of bacterial
processes! The pH of the yolk is 6.0 in fresh egg. Elevated yolk pH
indicates rotting.
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DISORDERS OF THE FRESH EGG
Disorders due to abnormal development of egg and to external
factors
The disorders of the fresh egg are present already at the moment of
laying. Though, these eggs are fit for human consumption but are
excluded from distribution.
The disorders of the shell are hollows, protrusions, disjunctions up to
distorted forms. The “candle-broken” egg is formed during the
development of the egg. Upon a mechanical effect, the developing
egg is ruptured, later further calciferous layers will cover this injury.
The disorder can be detected only by translumination. The
calcification of the shell is often disturbed due to the illness of the
oviduct or systemic disorder.
It is not a disorder but severe hygienic insufficiency if the shell of egg
is contaminated with faeces or blood.
Disorders of the yolk are the complete absence of yolk, the
presence of two or more yolks, the ovum may be separated in
different measure.
Sometimes spots can be seen on the vitelline that mostly is derived
from water closed under the vitelline membrane during development.
Sometimes, for unexplained reason, the yolk is greenish and is
called: grass egg. On the surface of yolk often red spots can be
observed deriving mainly from the oviduct. This is the blood spotted
egg. The meat spots are lighter in colour and are related to tissue
fragments derived from the oviduct and this is qualified similarly to
the blood spotted egg. Certain parasites may be found in the egg.
Though, they are not harmful but degustating.
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Disorders developing during storage
The vitelline membrane is thinning and might be ruptured during
storage. The result is the egg with mixtured yolk and albumen that is
not suitable for consumption. The dense part of albumen is diluted
and after a certain time only thin albumen is present (sticked yolkegg).
The water loss is gradually developing through the pores leading to
the enlargement of air space. This process, at 37 C and 50 %
relative humidity can reach the “air-dry” condition. An intermediate
state of the process is the swimming egg.
During storage, enzymes generate H2S, NH3 and volatile fatty acids.
The changes of pH were discussed earlier.
The egg is frozen at - 0.5 C and it becomes unsuitable for further
storage.
Avoid the big differences in temperature during storage, because the
egg is “sweated," promoting the proliferation of bacteria.
Sometimes the egg is spoiled during storage. The green rotting (in
basic medium) is caused by Pseudomonas species that are
penetrated into the egg from faeces. They cause also red rotting (in
acidic medium). The yolk becomes black and hard (black rotting),
the albumen is evil-smelling upon the effect of Proteus spp. (e.g.
vulgaris). Yeasts can also penetrate into the egg during storage.
In the fertilised egg, the germ may start developing at low storage
temperature of 37-38 C. Under this condition after a certain time the
embryo dies and the blood-ring egg develop that is unsuitable for
human consumption.
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The examination of the egg (BATCH examination)
Methods:
Translumination
Observation
Breaking up (Each 10th of sample is broken up)
Most of the disorders of eggs can be seen only if the egg is candled
(transluminated). This can be carried out individually or in industrial
scale. In the individual procedure, the egg is kept between the thumb
and forefinger of left hand in horizontal position and is transluminated
by light coming from a light source having slit. During
transluminating, the egg is turned around its horizontal and vertical
axises. In the industry, the transluminator is built in a defined point of
the belt-conveyor of classification. Approximately 100 eggs are
examined simultaneously and the work requires to have good
experience. Under normal conditions, the yolk and albumen parts are
closely homogenous materials, the yolk might be slightly darker. The
air space has a size described in the Standard.
The inside of the egg can also be examined after breaking it. By
opening the egg, it is possible to observe its organoleptic condition,
the arrangement of parts of yolk and albumen and determine the so
called indices. Rotting can be identified by translumination while
bacterial examination can be carried out only after breaking the egg.
In case of abnormality, the further inspection is individual.
Rotting is caused by micrococci, coliforms, aerobe sporular
bacteria, Clostridia and Flavobacteria. The spoilage of egg stored
in storage houses often is induced by moulds (penicillium,
cladosporium, mucor and aspergillus species).
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The egg of the hen may be infected with salmonella. The widespread infection of our poultry stocks is well known and it is
maintained by the feed.
Though, the juice-egg can be prepared in a special way to avoid the
contamination of the shell by faeces, yet the contamination with
some salmonellas may occur. Such a small number of microbes
usually do not cause food intoxication because of the lisosyme
content of the cuticle and albumen, furthermore the disinfection of
the shell before breaking and the storage at an appropriate low
temperature inhibit the proliferation of salmonellas.
A completely different issue is the non-fresh egg removed by
translumination on day 7 of hatching. It must not use for direct
consumption only for the preparation of juice-egg.
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Principles Of Judgement Of Eggs And Egg-Products
Former judgements
Egg
Condemned for human consumption
Infertile hen’s egg if it is withdrawn from the hatchery after the
th
7 day of incubation.
At withdrawal of hatched egg of other poultry-species
disregarding the day of withdrawal.
Broken and organoleptically disordered eggs, those that are
mould-spotted, rotted or having mixed yolk and albumen, blood-ring,
parasites or otherwise degusting.
Eggs infected with pathogen bacteria or the number of
facultative pathogen or saprophyte bacteria or the residue level is
over the predetermined value laid down in regulations or
contaminated with other foreign material.
Approved for human consumption (after heat-treatment)
If the egg or its shell is contaminated, ruptured or depressed, or
having reduced, swimming, floating yolk, or blood spotted or meat
spotted, or frozen.
Egg product
Condemned for human consumption
If the egg-preparation is prepared from water-bird’s egg or it
was treated with a prohibited compound (or it is added to the
preparation).
Principles At Trading With Egg Or Egg Products
Prohibited to sell of hatched, broken, washed or dry-cleaned
eggs in market place or at farm.
Eggs originated from different poultry species must not be
mixed during marketing.
Disinfected and unwashed eggs must not be mixed or
marketed as preserved egg. The fact of preservation must be
labelled on the collective-package.
Marketing non-hen’s egg, the name of the given species must
be written in an attention drawing manner at place of selling.
In case of duck or geese egg, the following massage board
must be constructed and exhibited (it is written with letter size of at
least 20 mm):
‘’The egg can be consumed only following 10 minutes of boiling
or after well-baking’’