Eggs- the "float" test tells their age, and more fun facts

Eggs are a delicious source of protein, and a staple of one of my favorite pastimes- baking! Getting fresh eggs at the Farmer's Market is a good way to support small farms, but raising hens for your own eggs is a wonderful experience for young and old alike. And the very best? Raising chickens that lay all different colored eggs! I adore my colored egg selection, from dark brown, pinks and cream, through to blues and greens.

How do chickens lay colored eggs? Well, it is in the genes of different breeds to lay certain colors of eggs. Chickens that have white eggs are simply creating a calcium shell with no pigments. Other hens, like my Americannas, coat the eggs with oocyanin, a by-product of the bile gland, making blueish eggs. Brown eggs are colored by a pigment similar to the haemaglobin in our blood, and it creates a rusty brown color. If you have chicken that is a crossbreed of these types, the brown and blue mix will create eggs of a greenish color. And many of the store-bought eggs we think of as white were actually a pinkish hue before the outer coating was washed off. Do colored eggs taste any different? Naw, but they are so fun to look at!

But what if you have chickens and you come across an egg and you don't know old it is? Perhaps you let them out to run in the yard and later find a pile of eggs under a bush. When did they lay them? Or one may even secret her eggs in the hen house, often from having "gone broody" and wanting to hatch them. Or maybe you have the problem that I do- when my chickens lay their massive glut of eggs in the summer, I try to keep eggs separated into cartons by age and use the oldest first. But...sometimes I lose track of which is the oldest when I have five or six cartons at a time. Well, never fear, you can figure out how old they are, and if they are past being safe for human consumption! What you need to do is "float" your eggs. This is a very old method to check eggs. Simply get a bowl or glass of room temperature water deeper than the eggs are tall, and place the questionable eggs in it.

The freshest of eggs will lay on the bottom, like the egg on the left, so you know it is just days old. The egg on the right has just one end lifted a bit from the bottom, so it is a week or so old.

These brown eggs are all lifted so that one end is touching the bottom of the bowl, but there is space under their sides, so they are possibly a week or two old. They will continue to rise as time goes on.

 Look at the eggs on the right. Compared to the fresh blue egg in the front, the brown one to the back is standing straight up, with only it's bottom touching the bowl. This means the egg is a several weeks old. As long as it is still touching the bowl it is fine to eat. Never eat an egg that floats above the base of the bowl. If you are unsure, put just that egg in a clear glass filled with water so you can hold it up and make certain the egg touches the base. As eggs age their shell's protection weakens and more oxygen is absorbed, while the egg is also losing enzymes. This makes the egg become lighter, tipping upward until it is finally completely upright. However, a floating egg shows the egg is very old, and can be a sign that bacteria has breached the eggshell and it is no longer safe to eat.

Here we have an egg on the left that is laying down- fresh. And one that is beginning to stand up on the right- a week or so old. And then we have the brown one at the bottom. I had a hen who was trickily laying her eggs in the top of the hanging feeder. I had no idea how long they had been there! Can you see this egg is floating? NEVER EAT AN EGG THAT FLOATS! And now you know how to tell the approximate age of your eggs, whether bought or raised.

We talked about how the genetic make-up of a chicken determines  the color of the egg's shell. However, external conditions influence the color of the inside of eggs. Most barnyard-raised birds with a varied diet have a higher amount of carotenoid (yes, like in carrots), and that is the chemical that makes the nice orange color in the yolks. I was making a wedding cake recently and had to buy extra eggs to supplement the ones from my hens. I was startled all over again to see the difference between the two. The bowls are identical, but on the left is an egg from my chickens, versus the store bought variety on the right. Mine has a gorgeously hued yolk compared to the insipidly pale one from the store. And, while the eggs were the exact same size in the shell, my yolk was almost twice as big! The color and flavor of the contents of eggs are directly influenced by the diet and living conditions of the bird that laid it.

I don't know if you've ever watched Nigella Lawson cook on television, but she always seems to have a beautiful bowl of eggs sitting on her counter. And, after visiting Paris, I realized that the eggs sold there were not refrigerated. Turns out that is common in Europe. Why? A fresh egg has a natural cuticle on the shell called a "bloom". It is designed to keep bacteria out of the egg. This is so that the egg is safe and healthy for a chick to grow in it. However, in America commercial eggs are washed prior to sale, and the "bloom" is removed, leaving the egg susceptible. Thus the eggs need to be refrigerated to keep them fresh longer. Freshly laid eggs that have not been washed or refrigerated can be left out safely for up to a month. So Nigella isn't just putting that pretty bowl out for the show, you really can keep your freshly laid, unwashed eggs out to admire.

And one last fun fact. Eggs can differ drastically. In the beginning, chickens sometimes lay a first egg that is considerably smaller than their normal egg size, then their body regulates. But occasionally you can also get what is called a "fairy egg". This is a very tiny egg that often has no yolk. This can happen when a hen reproductive system is disrupted, due to illness or a startling incident. The tiny egg above was laid directly after I removed a 6 foot black snake from the hen house. There were no eggs for several days, and then this little thing. When I "blew it" to keep, there was no yolk.

 To blow an egg to preserve it, punch a hole in both ends with a thick needle. Open a larger hole in one end and stick the needle into the egg and stir about to break up the yolk and white. Then put your mouth over the smaller hole and blow out the contents. You have to really do it hard to get all of it out. Then run water into the egg and blow out. Let it sit to dry and you can keep it indefinitely. 

Conversely, really old chickens begin to deposit calcium in less regular ways which can lead to "dinosaur" eggs that have lumps, bumps, and waves. And often the eggs get larger as the chicken reaches old age. And there you have it, Dear Reader! More than you ever needed to know about eggs ;)