The Science That an Egg has to teach.

You might be wondering what the title means, what science can a thing as simple as an egg teach us. Read on to know more.

Majority of us like to consume eggs in one form or the other ranging from boiled to poached to fried to scrambled. The dramatic transformation an egg goes through from its liquid raw state to its solid cooked state has always captured my attention and has led me to explore the “whats”, “whys” and “hows” of it. So here I am, sharing with you, my new found knowledge.

An egg consists of 2 parts – the yolk and the albumen. When you crack open an egg, the translucent liquid that you see is the albumen (egg white) that surrounds the generally yellowish yolk. It’s not at all necessary for the yolk to be yellow in shade, it largely depends on the diet the hen is on while laying the egg.

egg structureYou could imagine these 2 parts to be just sacks of water dispersed with proteins. To completely imagine the structure, you need to know how the proteins look like. Now this is where the science stuff begins. Protein molecules are basically made up of long chains of amino acids bound to one another by fairly weak chemical bonds.

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You might have this one doubt, i.e., if the composition of both yolk and albumen are the same, why does the raw yolk seem less runny than a raw egg white? I can say it is because the yolk contains some fat and this fat gets bound with the proteins and keeps them together. The runny nature of egg white can be attributed to the negative electrical charge of the proteins and as you know like charges repel each other. Hence we have the watery and loose egg white. Whereas in the yolk, the presence of fat is strong enough to withstand the repulsive force of the proteins.

Now as we start cooking, the egg gets heated up. All of its molecules start to move faster and collide with one another. As the temperature increases, the collisions become more intense resulting in the breaking apart of the weak chemical bonds holding the amino acid chains together. So now you will be having many short and loose protein strings. With further heat, these become entangled into some kind of a cobweb structure.

You might be wondering what happened to the water part of the egg during all this process? Well, the water has also got dispersed in the protein cobweb so it can no longer flow together, turning the liquid egg into a semi-solid. Continued heating causes more entanglement, leaving less space for the water. Eventually, much of the water is squeezed out (usually referred to as weeping) and evaporates, causing the egg protein to coagulate. When eggs are overcooked, the protein web becomes so tight and retains so little water that the egg white becomes rubbery and the yolk chalky. This difference is due to the fat interspersed with the protein web in the yolk.

So the story of conversion of a liquid to a solid in the presence of heat is the science which an egg has got to teach us all.

That is the end of this post. I would like to know how you feel about this post. Please do leave a comment below.

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Making those Perfect Boiled Eggs

How hard is it to make some perfect boiled eggs? I have witnessed a lot of people complaining about the boiled eggs turning out to be either too runny or too firm. Right now I have the perfect solution to rectify this problem and am going to share it with you right away. But firstly, let’s see how to make boiled eggs – the basic procedure.

Take out ‘n’ (where n = any natural number) number of eggs from the fridge and keep it outside so that they warm up to the room temperatures.
Place the eggs in a saucepan and fill with normal tap water covering the eggs by about an inch which means the eggs should be absolutely immersed beneath the water.
Set the saucepan over high heat, uncovered.
Bring the water to a full, rolling boil. You can identify this when bubbles appears on the water surface.
As soon as the water comes to a boil, remove the pan from the stove (very important) and keep the pan covered.
Now you need a stopwatch or a timer to decide how long you need to leave the eggs in the covered pan.
To decide on the time span, you need to identify what type of egg you would like to consume.
If you want soft-boiled eggs, then you will have to take out the eggs quickly.
If you want hard-boiled eggs, then you will have to leave the eggs in water for a while longer.

See the image below of a small experiment on boiled eggs where the results at each minute is clearly indicated.

EGG

The eggs change their texture from runny soft-boiled through to slightly runny soft-boiled through to firm soft-boiled through to creamy hard-boiled through to firm hard-boiled in minutes 1 to 18.

Now these minutes may vary depending on a number of factors like temperature, egg age, so on and so forth.
So you will have to determine the ideal minutes essential for obtaining what you desire for through repeated attempts and write it down.

Remove the eggs from the saucepan after the desired time has trickled away and place the eggs in a bowl of cold water.
Tap the shell using a spoon or hit it on a hard and smooth surface to crack open the shell.
Older eggs are actually easier to peel. This is because as an egg ages, its albumen shrinks and the space between the inner and outer shell membrane enlarges, which facilitates separating the membranes and removing the shell.
If you are using newer eggs, you should add salt in the boiling water while cooking.
Peel the egg shell off and enjoy the perfect boiled egg – the way you wanted it to be!