A customer brings back a dozen: two eggs have blood clots, one smells of fish. To her they’re “old eggs,” though they were laid yesterday. Most egg defects have nothing to do with freshness: the cause is the hen, the feed or the nest. Once you know where each comes from, most of them can be fixed on the farm instead of explained to customers.
Blood and meat spots
- A blood spot is a drop of blood from a vessel that ruptured while the egg was forming. It’s more common in pullets starting to lay and in older hens, under stress and with vitamin A shortage; the tendency is also inherited.
- A meat spot is a brownish or whitish bit of tissue or protein that broke off in the oviduct.
Such eggs are safe to eat, but they look bad. Spots are found by candling; they’re harder to see in brown eggs, so more of them slip through. How to grade eggs for sale is covered in storing and grading eggs.
Dirty eggs
A dirty shell is almost always about the nest and collection:
- too few nest boxes, so hens lay on the floor (how many you need);
- dirty or wet nesting material;
- hens sleeping in the nests and soiling them — perches must be higher than nests;
- collecting once a day instead of two or three times;
- diarrhea in the flock — a reason to check feed and health.
In the EU, Class A eggs may not be washed: washing removes the shell’s protective coating. Where washing is allowed, the rule is simple: the water must be at least 11 °C (20 °F) warmer than the egg and no colder than 32 °C (90 °F). Cold water makes the contents contract, pulling dirt and bacteria in through the pores. Never soak eggs, and dry them right after washing.
Light soiling comes off with a dry sponge or fine sandpaper. Heavily soiled eggs are better not sold.
Pale yolks
Yolk color depends on pigments in the feed, not on how nutritious the egg is. On wheat and barley without greens, yolks are pale; corn, grass, alfalfa, pumpkin and carrots make them yellow and orange. If customers want a “farm” yolk, it comes from the ration, not the breed. What you can add to the diet is in the greens and extras article.
Runny whites
- Egg age and warm storage are the most common cause: the white thins every day at room temperature.
- Hen age — older hens lay thinner whites.
- Infectious bronchitis — runny whites together with misshapen, wrinkled shells in many hens at once. That’s a reason to call a vet (on respiratory disease).
Off odors
| Smell | Possible cause |
|---|---|
| Fishy | Fish meal above 3–5% of the feed; rapeseed meal in some brown-egg strains |
| Onion or garlic | Lots of onion and garlic in the diet |
| Musty or chemical | Storage next to fuel, disinfectants or onions; eggs absorb odors through the shell |
On rapeseed meal and fish meal, see replacing soy.
Shells
Thin, soft, rough and wrinkled shells are a big topic of their own, from calcium and vitamin D₃ to flock age and disease. They’re covered in the thin shells article, and double yolks in a separate article.
Defects in your records
In EggPulse dirty and cracked eggs are recorded separately at collection, and the weekly summary shows the share of cracked and defective eggs. If it rises, line it up with dates: nesting material changed, new feed, flock age.
