Membranes of backyard eggs vs. store-bought eggs

[K0k0shka]

Do you guys notice a difference in the toughness of the membranes of your own eggs vs. store-bought eggs? I've noticed that our eggs have really strong membranes that take quite a bit to break when cracking eggs to cook. This isn't a problem for me, because I just use my fingernails to pierce the membrane, but my husband keeps his nails trimmed to the point of being non-existent, and he's quite annoyed that he can't bust that membrane open He has to press really hard, at which point he smashes the shell into bits and the bits get into the egg and in the pan. Store-bought eggs' membranes are very easy to break, almost like there's nothing under the shell at all. Have you noticed this? Do you know what the explanation is? Is it because of freshness? It's a bit contradictory because my husband also complains that our eggs are not as fresh as store-bought, because I don't refrigerate them and he says they degrade faster. Which I'm sure they do, but they rarely go more than 3-4 days before being eaten, so I doubt 3-4 days at room temperature would really ruin them. So, our eggs are too fresh (because of the membrane) and not fresh enough (because of room temperature) all at the same time, and I'm not sure how to respond to all that, other than being politely annoyed

 

[DonyaQuick]

Oh yes! Once my chickens were laying regularly that was something that really stood out to me, both the tougher membrane and seemed like sturdier shells too in some cases. The yolks also seem a lot less prone to breaking. I haven't kept any eggs long enough to know if it's just down to freshness, lack of refrigeration, or something else.

 

[U_Stormcrow]

I assure you, store bought eggs aren't under refrigeration until they've been gathered, washed, sanitized, and packed. USDA allows them to sit around for several weeks prior to that occuring, and still make Grade A for human consumption (assuming they also pass the candling test, of course). How long they then remain in storage before being warehoused by the supermarket chains before then making a store shelf is also quite variable.

and look to your feed. The two most important Amino Acids in chicken development are Methionine and Lysine, they appear on a US guaranteed nutrition label. They are KEY to the development of young birds, and their long term conditon overall. The third most important AA is Threonine, which sadly doesn't have to appear on labels. Threonine is a huge component of membranes such as those at the shell barrier and surrounding the yolk, working with Methionine to produce strong connective tissues.

Pound per pound, fish meal, blood meal, brewers yeast, meat and bone meal, soy, flax, field peas are all high in threonine - they are also relatively more expensive than corn, and likely found in very low quantity in commercial chicken feeds intended to minimize egg production costs (at the expense of the long term health of the birds, which they don't plan on keeping). Those ingredients are much more present in feeds for us backyard keepers.

 

[themotleycoopchic]

I how much I learn on this forum! I find it all so educational and interesting.

 

[K0k0shka]

I assure you, store bought eggs aren't under refrigeration until they've been gathered, washed, sanitized, and packed. USDA allows them to sit around for several weeks prior to that occuring, and still make Grade A for human consumption (assuming they also pass the candling test, of course). How long they then remain in storage before being warehoused by the supermarket chains before then making a store shelf is also quite variable.

and look to your feed. The two most important Amino Acids in chicken development are Methionine and Lysine, they appear on a US guaranteed nutrition label. They are KEY to the development of young birds, and their long term conditon overall. The third most important AA is Threonine, which sadly doesn't have to appear on labels. Threonine is a huge component of membranes such as those at the shell barrier and surrounding the yolk, working with Methionine to produce strong connective tissues.

Pound per pound, fish meal, blood meal, brewers yeast, meat and bone meal, soy, flax, field peas are all high in threonine - they are also relatively more expensive than corn, and likely found in very low quantity in commercial chicken feeds intended to minimize egg production costs (at the expense of the long term health of the birds, which they don't plan on keeping). Those ingredients are much more present in feeds for us backyard keepers.

Mine eat Purina Flock Raiser. What does that mean for the membranes? Isn't that roughly what commercial chickens eat, too? A commercial mass-produced feed with no claims to anything fancy and expensive.

 

[U_Stormcrow]

Mine eat Purina Flock Raiser. What does that mean for the membranes? Isn't that roughly what commercial chickens eat, too? A commercial mass-produced feed with no claims to anything fancy and expensive.

Purina Flock Raiser is one of the better commercially available feeds. Compared to what's offered factory hens, it is MUCH higher in total protein, much higher in methionine, lysine, threonine, and a number of key vitamins and minerals. Overall, a more balanced feed. A number of additional inclusions which are more geared towards backyard keeping than selling to make poultry by-product meal around a year and a half of age.

There is a HUGE difference between the "pet food" market (i.e. Purina Flock Raiser) and the feeds manufactured for Tyson, Wayne Farms, etc whose sole purpose is to provide a feed just expensive enough that losses due to reduced egg size, reduced rate of lay, higher chicken mortality don't exceed the cost of improving the quality of the feed itself. Yes,they both enjoy economy of scale, but they are geared for different market segments.

 

[K0k0shka]

Purina Flock Raiser is one of the better commercially available feeds. Compared to what's offered factory hens, it is MUCH higher in total protein, much higher in methionine, lysine, threonine, and a number of key vitamins and minerals. Overall, a more balanced feed. A number of additional inclusions which are more geared towards backyard keeping than selling to make poultry by-product meal around a year and a half of age.

There is a HUGE difference between the "pet food" market (i.e. Purina Flock Raiser) and the feeds manufactured for Tyson, Wayne Farms, etc whose sole purpose is to provide a feed just expensive enough that losses due to reduced egg size, reduced rate of lay, higher chicken mortality don't exceed the cost of improving the quality of the feed itself. Yes,they both enjoy economy of scale, but they are geared for different market segments.

So the membranes are more likely thicker because of better nutrition, not necessarily freshness? I guess I could test that by letting some of our eggs sit around for a couple of weeks (refrigerated).

 

[U_Stormcrow]

Oh, the 4th most important Amino Acid (also not appearing on a US nutrition label)? Tryptophan.

and its basically impossible to build a corn and grain-based feed which is deficient in Tryptophan. You would have to work really, really, really hard at it to do so, and you would almost certainly be more deficient in a more important AA as well.

Its one of the reasons I rarely mention it. Its related more to maintenance and things like niacin levels rather than development, and (unlike Met, Lys, etc) a bird's needs for it don't decline as it progresses from hatchling thru juvenile, adolescent, past point of lay and into adulthood.

 

[U_Stormcrow]

So the membranes are more likely thicker because of better nutrition, not necessarily freshness? I guess I could test that by letting some of our eggs sit around for a couple of weeks (refrigerated).

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.

 

[U_Stormcrow]

and to be clear, I am NOT an expert, just someone who has read a bit.

For instance, a few of my ducks produce shells its near impossibble to break (normal for ducks - much stronger, on average, than chicken shells) with very strong outer membranes at the shell barrier, but relatively weak membranes at the yolk. Which varies seasonally. That tells me it relates to their diet while free ranging - something they get part of the year from the pasture which their commercial feed isn't providing. But what it is requires more chemistry than I'm comfortable with.