EGG QUALITY
BLOOD STAINS ON SHELL
First quality eggs, as defined by egg marketing authorities, are those that are well-formed, with clean, uncracked shells, with an air cell that is not more than 5 millimetres in depth and with a yolk colour not less than No. 10 on the DSM Yolk Colour Fan”.
THE EGG SHELL
It is important that eggs be uncracked and kept very clean and dry, as bacteria from dirt and stains can penetrate even through an unbroken shell.
SHELL COLOUR
There is no relationship between the colour of the shell and the quality of the egg, its flavour or “cookability”. Commercial hybrid hens can lay either white-, tinted- (creamy coloured) or brown-shelled eggs. Brown-shelled egg laying hybrids are now the most commonly farmed hens.
The incidence of blood stains on the egg shell occurs more frequently with young birds, though it is quite usual with any aged bird when a double yolker is laid. The shell is stained when small blood vessels that line the oviduct rupture when an egg passes through, though subsequent eggs are generally free from any stains.
Note: Blood-stained eggs could also indicate cannibalism within the flock and it is especially important to investigate and check each bird for possible injury around its vent.
YOLK COLOUR
Carotenoid pigments derived from plants consumed by the bird accumulate to pigment the egg yolk. Although orange yolks look good, there is very little nutritional difference between paler yellow and darker orange yolks.
Pasture and vegetable scraps can contribute a range of carotenoid pigments to the hens’ diet. These can be variable, hence yolk colour is likely to vary when hens are given access to a variety of feed sources.
BLOOD OR MEAT SPOTS
Some may find blood or meat spots to be unsightly. However, they present no harm to the consumer and can be easily removed. When a mature yolk is released from its follicle in the ovary, the follicle usually bursts along a line (the stigma) that contains few, if any, blood vessels. If the follicle does not tear exactly along the stigma a tiny blood vessel may be torn and escaping blood may form a “blood spot” in the egg.
Some breeds of laying birds have a genetic tendency to lay more eggs with blood spots. Also, you can expect a higher occurrence of blood spotting in young hens just coming into lay.
Albumen (egg white) is formed around the yolk as it passes through the oviduct. “Meat spots” are thought to be pigmented or non-pigmented pieces of albumen left behind during formation of the previous egg. The pigment involved (Ooporphyrinse) is associated with colouration of brown-shelled eggs; hence meat spots are less common in white-shelled eggs.
Occasionally, meat spots are made up of pigmented epithelial cells that line the oviduct. Unlike blood spots, meat spots tend to show a random incidence throughout lay with no age-related effect. However, birds that tend to lay eggs with meat spots are likely to continue to do so throughout lay.

FRESHNESS
The best way to prolong freshness is to promptly collect eggs and store them in a refrigerator. As a rule of thumb, as much freshness is lost in three days at room temperature as in three weeks in the refrigerator.
Fresh, well-stored eggs are more flavoursome, produce firmer cakes and custards and the whites beat up to produce stable foam. The moment an egg is laid it contains no air cell, though as it cools and loses moisture, a slight vacuum is created serving to draw in air through the pores in the shell.
As the egg ages, this air space becomes bigger. You can use the following as a guide on hard-boiled eggs:

RUNNY ALBUMEN
When a fresh, well-stored egg is fried, the albumen is more likely to stand high and close to the yolk rather than spread across the pan. Runny albumen can be caused by a number of factors including genetic tendency, age, health and nutrient intake.
Albumen tends to become runnier as the hen gets older and when intake of key nutrients such as protein is compromised. It is important to provide young stock with shelter and water, especially during hot weather, to avoid a severe reduction to feed intake (see Poultry Housing).
It is also important to offer ample feed and avoid diluting balanced Barastoc feeds with poor quality forages at any time. Illnesses such as Infectious Bronchitis, whilst presenting no threat to human health, can be detrimental to albumen quality.