Why do boiled quail eggs turn black in some places?

From ancient times to the present, health has always been an instinctive pursuit of human beings.

Not long ago, there were some claims in the circle of friends that "the blue-black membrane on the boiled egg yolk can cause cancer", which sparked heated discussions among the majority of netizens. So what exactly is that "black film" on the cooked egg yolk? Does it really cause cancer when consumed?

First of all, we need to know, what substances and ingredients are in egg yolks?

After research, it has been found that among the main components contained in egg yolk, protein accounts for 48%, water accounts for 48%, minerals account for 2%, and egg yolk also contains a variety of vitamins and other trace elements.

These trace elements are the main reason why the surface of the egg yolk turns blue-black after cooking. Studies have shown that egg yolks contain high amounts of phosphorus, iron, and lecithin.

Among them, the iron element.

It is one of the "culprits" that causes the hard-boiled egg yolk to appear blue-black.

The protein in egg whites generally contains sulfur, and the substance has a denaturation process in which sulfur meets hydrogen and combines to produce hydrogen sulfide.

Hydrogen sulfide is a toxic gas and the taste of the so-called "rotten eggs" that we often call in our mouths. But don't worry, a small egg contains very little hydrogen sulfide, and there is no real harm to human health.

But it's boiling eggs.

According to the principle of heating, the heat enters from the outside to the inside, so the first thing that changes is the egg white, and the egg white has its own solubility as the temperature increases.

As it decreases, hydrogen sulfide is forced into the yolk.

At the same time, the iron in the yolk is changed, and the iron is released and stripped from the yolk high-phosphoprotein during the heating process. Right at the junction of egg yolk and egg white, iron ions react chemically with hydrogen sulfide.

2Fe3++H2S = 2Fe+S+2H+, which eventually forms ferrous sulfide. Ferrous sulfide has a grayish-green appearance, so the surface layer of the egg yolk has a blue-black color. And the longer the egg is boiled, the darker this layer of green will be.

After really understanding what the blue-black layer on the outer edge of the boiled egg yolk is, everyone must be more concerned about whether this ferrous sulfide is harmful to the human body, or whether it can cause cancer as circulated on the Internet.

Experts say ferrous sulfide itself is non-toxic and harmless, and it is insoluble in water. In 100 grams of eggs, only 7 mg of iron is contained, and it is impossible to convert all of them into ferrous sulfide, so the ferrous sulfide in eggs can only be described in trace amounts, and sulfur is very not easy to be absorbed by the human body, so even if it is eaten, it will basically follow the human digestive system.

is metabolized out.

On the whole, eating the blue-green egg yolk after cooking is not harmful to the body, and it will not cause cancer. So, please feel free to eat it.

If you are clear, it will not be black, only the kind of tea eggs, and then it will be organized and blackened. Well, if it's clear that it's blackened, it means that your harness has deteriorated. Don't eat it.

The quail eggs are boiled black because they are too old and have begun to spoil.

It may be broken, or it may be that it has been boiled for too long, as long as the yolk is not blackened, it is fine.

Answer: There are black spots in the boiled eggs, which means that the eggs have been stored for a long time.

Boiled quail eggs are blackened in some places, and quail eggs are not very fresh, if they are only white, they can be eaten if they are removed.

This is the quail eggs you buy have deteriorated, so they will appear black after cooking, this is not recommended to eat, because it is not fresh.

What happens to quail eggs that are gray when cooked? It should be normal, I often boil quail eggs to eat, but this phenomenon is also there. The shell of a quail egg is mainly composed of calcium, which must be formed by the uneven distribution of calcium on the top of the eggshell.

Boiled quail eggs stink can be caused by:

In terms of the ingredient list, possible reasons include:

1.Spoiled quail hungry eggs or stale ingredients were used.

2.Spices (such as dried chilies, cinnamon, star anise, cardamom, grass fruits, peppercorns, bay leaves, etc.) have spoiled or are of poor quality, resulting in an off-flavor appearance of boiled quail eggs.

In terms of production steps, possible reasons include:

1.Quail eggs are not cleaned and may have some dirt or bacteria attached to them, which produce an odor after being boiled.

2.During the cooking process, the order or amount of spices is not appropriate, resulting in an off-flavored smell of boiled quail eggs.

3.Cooking for too long can cause quail eggs to be cooked or develop an off-flavor.

To avoid this, the following measures can be taken:

1.Make sure you use fresh, high-quality ingredients.

2.Wash quail eggs carefully to ensure that the surface is clean.

3.Add the spices in the correct order.

4.Master the correct cooking time to avoid quail eggs from boiling rotten.

Just throw it away. If the quail eggs are stinky and sour due to bacteria, it means that they have deteriorated and can no longer be eaten, so you can discard the cave directly. There are many ways to eat fresh quail eggs, such as eating them directly after cooking, marinating quail eggs, salt-baked Nazai quail eggs, boiling them in a hot pot and eating them, etc., each of which is very delicious and delicious, and the eggs are full of flavor.

1. Avoid eating quail eggs with shiitake mushrooms.

Don't eat shiitake mushrooms while eating quail eggs, the two may react, increase the chance of dark spots on the face of female friends, and have a great negative impact on their appearance.

2. Eat quail eggs and don't drink carbonated drinks.

While eating quail eggs, don't drink some carbonated drinks carbonated drinks, which may react with quail eggs to form chemicals, which are not easy to be digested and absorbed by the human body, and may also cause symptoms of abdominal pain, and may also cause stomach cramps, which will bring great pain to yourself.

3.Quail eggs cannot be eaten at the same time as prawns.

At the same time, do not eat some seafood at the same time as eating quail eggs, especially some prawns, prawns are hair food, and quail eggs at the same time may also have a great negative impact on their own gastrointestinal and digestive system, many patients and friends in the quail eggs at the same time to eat seafood may also lead to their own poisoning coma, very serious.

Hello, glad to answer for you: this may be due to the fact that the quail eggs are not fully cooked or have been stored for too long, causing the yolk to oxidize and turn black. It is recommended to add some salt or white vinegar to help the shells peel off more easily when boiling quail eggs, and to eat them in time after cooking.

If the eggshell is peeled off, the egg is buried black, and it is best not to eat it, so as not to affect health.

Can quail eggs be stored in the refrigerator.

Yes, quail eggs can be stored in the refrigerator. Quail eggs that are kept fresh in the refrigerator can be kept fresh for a longer period of time, usually for about 2-3 weeks. When storing quail eggs, you can place them in an airtight container to prevent odors and moisture from entering the inside of the quail eggs.

It is important to note that the shell of quail eggs should be cleaned before storing them to avoid bacteria entering the inside of the eggshell and causing spoilage. At the same time, when refrigerating quail eggs, it is also necessary to avoid mixing them with other foods to avoid contamination.