Is it a myth that water removes an egg's bloom?

[chickendadva]

What do you think? Is it a myth that washing eggs with water removes the bloom? Am I misunderstanding something? What if the protective quality of the bloom is compromised by water even if the bloom isn't removed? (Guess I could try to research that too.)

A couple of things, which are supported by your research

The bloom is supposed to form a waterproof seal around the egg as water is the most efficient mode of travel for bacteria. So...how can something that is supposed to be waterproof be rinsed off by plain water?

Second the bloom is not a foolproof shield. This is evidenced by the number of people who still get rotted eggs that didn't wash.

Third the bloom is designed to break down as the chick forms and needs to exchange respiration gases through the pores of the shell. This happens in 14 to 21 days regardless of whether you are growing a chick or not.

4th the bloom is a soft tacky mucous membrane that quickly dries and hardens after laying. This is why nesting material sometimes sticks to the egg. Any foreign substance the egg comes in contact with before it dries can compromise the bloom. So that poop on the egg may have already wiped off part of the bloom before it dried. Rule of thumb, if you can't wipe off the poop with a little light scrubbing there is a good chance that the poop has compromised the bloom. If you don't want to wash it, use the "water glassing" method of storing them in a hydrated lime-water solution at room temperature. The hydrated-lime will kill the bacteria in the poop but not penetrate the shell. This of course will be not kill the bacteria if its already penetrated the egg, but if you use a large enough container these eggs will automatically become buoyant and float when the yolk is eaten by the bacteria.

 

[Altairsky]

It is forbidden in EU to wash eggs. Eggs in EU are safe to be eaten a la coque, which means still raw on the inside.
Eggs in America are washed. In US it's strongly advised to cook them until they reach 165°F for at least 1 second (which is an insane temperature for us italians). I prefer my eggs to be bolied 1 minute and drink them raw.

I think this tells everything about the cuticle. US eggs are even banned from most EU countries for this very reason. Washed eggs are considered unsafe to eat because cleaning them destroys the bloom.

 

[HSoto]

A lot of people seem to think that rinsing an egg with plain water will wash the protective bloom/cuticle off. I've always thought so too, but then a post on Instagram questioning this caught my attention and I decided to research it. Now I'm not so sure.

There are various studies researching washing eggs with various chemicals and detergents. I only found one that actually tested with plain water (albeit on quail eggs, not chicken eggs):

https://europepmc.org/article/med/32731973

Click to read the full text and look at Table 2. You'll see that water and sodium hypochlorite didn't seem to remove the cuticle. Both seemed to affect it slightly, with sodium hypochlorite having more of an effect, but neither removed it. All the other substances used did remove the cuticle.

Here's another study:

https://www.sciencedirect.com/science/article/pii/S0362028X22115528?via=ihub

In this one, eggs were washed with a mix of water and detergents. It didn't seem to affect the bloom/cuticle. This was their conclusion:

"We could find no evidence to suggest that the washing procedure used in this study irreversibly changed the cuticle quality of eggs from the end of lay, which inherently had poor cuticle coverage (worst-case scenario). This conclusion was valid for both brown and white eggs and was based on the assessment of the cuticle coverage, using a dye, and on the cuticle quality criteria as assessed by SEM. Moreover, within each group of eggs, a lot of variation in cuticle coverage and quality naturally occurred."

A third study:

https://www.sciencedirect.com/science/article/pii/S0032579119495928

This had a variety of findings:

1. Cuticles vary by hen. Some hens lay eggs with very little to no cuticle. Other hens lay eggs with a cuticle covering most, but not all of the egg.
2. Hen age didn't seem to make a difference. (Which was interesting, because the study I linked to first contradicted this.)
3. Brushing/scrubbing eggs can damage the cuticle.
4. The cuticle deteriorates naturally with age.
5. Spraying eggs with chlorine dioxide did not affect the cuticle.
6. Manure did affect the cuticle.

So, based on that, if you try to scrub dirt/poop particles off with a brush and without water, there's a chance you might be damaging the bloom more than if you washed the egg.

An article (not a study):

https://www.cfsph.iastate.edu/thelivestockproject/eggs-is-washing-and-refrigerating-necessary/

This says, "Using a chlorine-based sanitizer between 50-100ppm protects the cuticle of the egg while sanitizing." Not sure what their source is. It also says, "Warm water allows the egg to expand and push bacteria out, but cold water pulls the bacteria in."

Hatching & Brooding Your Own Chicks (Gail Damerow) says:

"You don't want to wash the eggs, for fear of removing the protective bloom, but you might dip them into a sanitizer. Some poultry keepers routinely sanitize all hatching eggs, which does not affect the bloom and does improve the hatch rate. . . . Never use water that's cooler than the eggs, because it can force contamination through the shell. Dip the eggs in the sanitizer for at least 1 minute but no more than 3 minutes, then set them on a clean towel to air dry; do not rub them dry, which would rub off the bloom."


What do you think? Is it a myth that washing eggs with water removes the bloom? Am I misunderstanding something? What if the protective quality of the bloom is compromised by water even if the bloom isn't removed? (Guess I could try to research that too.)

We have had upwards to 30 chickens and whenever we get a lot of rain it gets very muddy outside in their pen. So they bring in a lot of poop and mud and get our eggs all dirty. Sometimes they'll be clumps of poop since they only prefer to use five of the 10 nesting boxes. I wash generally about a third in just regular water and wipe off nasty spots. I can't say for sure whether or not it takes off the bloom, but I have never really noticed much of a difference between washing them in water and not washing them at all. I do try to use up the washed ones sooner but really I haven't noticed much of a difference