Membranes of backyard eggs vs. store-bought eggs

[K0k0shka]

Both.

Imagine making "Jello" or cheating a merangue with more gelatin (better nutrition). You get a firmer product. But as time passes, it begins to degrade. Same thing going on here, though more processes, and more complicated processes. Temperature has a component. Porosity of the eggshell has a component. Surface area of the egg relative to volume. Humidity. Others. But those are the biggies - how healthy was the laying hen's diet, under what temps is the egg kept, how rapidly is moisture lost thru the shell into the surrounding environment.

It’s a complex equation. Thanks for all the info!

Speaking of porosity, store-bought eggs have noticeably more porous shells, with white eggs being the most porous. I see this every year around Easter. I dye a lot of eggs, and I find it hard to get a nice uniform color with store-bought eggs. They suck in too much dye through their pores and leave a pattern of pale dots on the shell. White eggs are the worst, they look like a whole mosaic pattern! While my backyard eggs get a nice even color. This is probably nutrition-related too, right? Maybe calcium levels? This was especially noticeable about 15 years ago. We jokingly called them “recession eggs” They were just ridiculous. Very brittle, too. Especially the white ones. It got better over time, but it’s still hard to get an even color.

Here’s a picture from way back then, of some recession eggs. The blue and green ones were supposed to be solid color. The pattern was entirely created by the porous shell. White eggs. The red one was a brown egg, it looks okay (had minor patterning on the underside).

I wonder why white eggs are worse? Breed variation? Can’t be nutrition, because I’ve tried different brands/farms over the years, including brown and white eggs from the same brand/farm, and the white eggs are always more porous.

 

[U_Stormcrow]

Brown (and Blue and "Green" [really Brown + Blue]) eggs come pre-dyed, straight out of the chicken. A chemical called protoporphyrin for brown eggs, which has some similarities to hemoglobin and chlorophyll. and biliverdin for blue shells. There's really complicated genetics involved which I won't pretend to understand - thus the variations in colors from white to almost red brown - but in essence, some of the pores in the calcium carbonate matrix that is the main component of an egg shell are already filled by chicken produced "dye", resulting in more uniform egg whne you add more dye to it.

And phosphorus levels in the chicken's diet helps it make very uniformly structured eggs. As do a number of other factors, including stress. making egg shells takes time - it works best when there are no interuptions, no feed restrictions, and the chicken is calm while doing so.

 

[K0k0shka]

Brown (and Blue and "Green" [really Brown + Blue]) eggs come pre-dyed, straight out of the chicken. A chemical called protoporphyrin for brown eggs, which has some similarities to hemoglobin and chlorophyll. and biliverdin for blue shells. There's really complicated genetics involved which I won't pretend to understand - thus the variations in colors from white to almost red brown - but in essence, some of the pores in the calcium carbonate matrix that is the main component of an egg shell are already filled by chicken produced "dye", resulting in more uniform egg whne you add more dye to it.

And phosphorus levels in the chicken's diet helps it make very uniformly structured eggs. As do a number of other factors, including stress. making egg shells takes time - it works best when there are no interuptions, no feed restrictions, and the chicken is calm while doing so.

Very interesting, thanks!

I take this to mean that my chickens are happy, if they are producing such beautiful, uniform eggs