Can You Over Boil an Egg? Is Cooking It a Chemical Change?

All of us love eggs, and boiled eggs have different levels. If we start counting the reasons why you should love eggs and eat them, there are several of them.

Eggs are an excellent source of lean protein, choline, iron, and minerals that are necessary for human nutrition. Besides, eggs are a metabolism booster, and this is why you can eat eggs even at night.

When it comes to boiled eggs, imagine yourself sitting beside your room’s window during a freezing cold night and it snowing outside.

A hot cup of coffee or tea, accompanied by a boiled egg, is all you can want for yourself. As it’s a metabolism booster, it fastens up your metabolism and makes you feel warm during cold weather.

We can write a complete thesis about the good things about boiled eggs. However, today’s article is all about boiling an egg and how does an egg changes physically & chemically when boiled.

Besides, we overcook an egg while boiling it every now and then. We will answer if it’s safe to eat such an egg and can you be fearless about an overboiled egg. So let’s get into it.

How To Boil An Egg?

First of all, let’s talk about boiling an egg. We will talk about the standard way of boiling eggs besides going into variations all of us bring to boiled eggs.

  • Wash the eggs and place them in a pot filled with cold water. You can take as many eggs as you want. However, there is a water quantity standard according to the number of eggs. The water level should be 1 inch or more above the eggs.
  • Turn on the stove, and let the water boil. 5 to 10 minutes will be enough for the eggs to be boiled completely.
  • Turn off the stove, and remove eggs from the pot. You can peel it off if you want to have it hot. Otherwise, keep it in a bowl of ice before peeling the shell off.
  • Finally, peel off the eggshell and enjoy it as you want.

Variations Of Boiled Eggs

Usually, there are two variations of boiled eggs common to everyone. We’re not including the overcooked boiled eggs in these variations because it’s an accident in most cases.  

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The method of boiling an egg we’ve shared above is exactly how you get a hard-boiled egg. The hard-boiled egg is completely cooked, and it has a soft, rubber-like consistency.

Boiling an egg for 10-12 minutes is enough to get the hard-boiled egg. There are numerous ways hard-boiled eggs are consumed around the world.

Soft Boiled/ Half Boiled

Now, this is what is more interesting. The rubber-like egg white with tripping and runny yolk enclosed is more fascinating to watch than to eat.

The soft-boiled or half-boiled egg is ready to be served in half the time it takes to boil an egg to full. It will take around 5-6 minutes for an egg to be soft-boiled.

Process An Egg Go Through During Boiling

Let’s have a sneak peek of what happens when an egg is put in a pot to get boiled.  

Well, we all know that eggs are a rich source of protein, and here is what happens to an egg when it’s boiled.

The rubbery structure of boiled eggs is due to the protein linking. When you start boiling the egg, the heat reaches the egg, and the coiled-up protein molecules start uncoiling. These uncoiled proteins find other proteins and form linkages with one another.

It results in a three-dimensional lattice. As more and more proteins start linking to form 3D structures, the formation of the egg starts changing from liquid to firm. The longer you boil eggs, the more firm and rubbery texture you’ll get in the boiled egg.

Is Cooking Egg A Physical or Chemical Change

From the above discussion, you can see that there is a physical and chemical change in the boiled egg. However, it’s hard to tell which one is more dominant. Let’s understand the change in the egg when it’s boiled.

A chemical change characterizes the change in the formation of a substance. If a substance transitions to become another substance, such changes are chemical ones.

The chemical changes can’t be reversed back. You can’t convert burnt wood into fresh wood, and it’s an example of chemical change.

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On the other hand, a physical change leads to a change in the state of the product without changing the chemical composition. Some physical changes might be reversible.

The example of freezing water and melting it back is the best example of physical change.

If we analyze a boiled egg, the previously existing protein bonds and coils are uncoiling to form new linkages and give a new structure to the egg.

Therefore, boiling will be categorized as a chemical change. Besides, you can’t reverse the change and turn a boiled egg into a runny egg.

Even when an egg is used in other cooking options like baking, the egg completely loses its properties, loses its state as an egg, and becomes just an ingredient. 

How Long Should An Egg Be Boiled?

There is nothing as such about boiling time when it comes to eggs, most people argue that the boiling time of an egg is not fixed and doesn’t matter.

However, truth is something else. The standard time required to boil an egg is 10-12 minutes. For a soft-boiled egg, 5-6 minutes are enough.

If you want to cook the yolk and white slightly, anywhere between 3-4 minutes is appropriate. If you exceed the time, the egg becomes more firm and rubbery as the chemical changes occur.

Can You Over Boil An Egg?

When it comes to safety, you can over-boil an egg. There is no harm in overboiling an egg until there is enough water and the egg doesn’t get burnt. However, the technical aspects of overboiling an egg are yet to be discussed.

Until and unless you’re using fresh eggs for boiling, there is nothing as such to worry about. Fresh eggs do not cause any harm if overcooked or overboiled.

Besides, anyone allergic to eggs should also not be messing around with eggs regardless of being over-cooked or undercooked. There is no evidence of fresh overcooked eggs causing health conditions.

Are Overcooked Boiled Eggs Safe To Eat?

Now comes the real question.

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Many people question if it’s safe to eat an overcooked egg? Although we have answered the answer indirectly, let’s get into one or two details for your understanding.

Arguments raising about the overcooked boiled egg surface based on the production of sulfur oxide in the egg when it’s overboiled.

However, all the research has supported the fact that sulfur oxide produced in the overboiled eggs is not beyond the allowed limit. Therefore, there is no risk associated with eating an overcooked or overboiled egg. It is completely safe to eat.

However, eating too much overcooked boiled eggs can lead to problems. Besides, the freshness of eggs is important to consider eggs being safe to eat.

Why Has An Overboiled Egg Green Layer?

When you’ve overboiled an egg, you might have noticed the formation of a green layer outside the yolK. Sometimes, it can be a gradient of green around the yolk. What is it?

We already discussed the formation of sulfur oxide when you overboil an egg. It happens due to the egg releasing hydrogen sulfide when overcooked. The hydrogen sulfide present in the overcooked eggs makes the green film or layer around the yolk.

What exactly happens is that the sulfur in egg white reacts with iron in the yolk to create iron sulfide. It’s created at the boundary of the egg white and yolk.

The green-colored layer you find around the yolk of an overboiled egg is due to the sulfides of iron and hydrogen. However, it’s not harmful to health if you’ve used fresh eggs. 

Final Thoughts

You can eat eggs in any way you want: boiled, scrambled, baked, or used as an ingredient in soups & culinary. However, it’s always safe to be careful when cooking.

Don’t boil the eggs for more than 10-12 minutes. Although there are no harmful effects associated with the overcooking or overboiling of eggs, it’s always good to stay on the safe side.

We hope this information has cleared many doubts and ambiguities popping in your mind regarding eggs.