Last Updated on September 16, 2022
If you’ve ever wondered why an egg changes color and texture when heated, read on. The reason is the same as for any other food: the proteins in egg whites change shape and become insoluble when heated. This process is called denaturation. The heat alters the amino acid sequence, which causes the egg proteins to lose shape and become insoluble. It also causes a chemical reaction known as an electrochemical reaction.
Proteins in egg whites denatured by heat
Heating and boiling eggs causes a process that denatures the proteins in egg whites. The heat causes the proteins to fold in such a way that they no longer have an inflection point. The proteins in egg whites take on a more solid state by unfolding in the water. This is called denaturation and denatured proteins become less soluble in water. While boiling the eggs denatures the proteins, it does not destroy the egg’s structure.
Cooking eggs causes denaturation, which is the process of dissolving a protein’s natural coiled state. Eggs are the most common culprit as they denature proteins at 184°F, but other factors such as heat, acids, and alkalies may also cause denaturation. Unlike the egg white’s gel-like texture, a denatured egg’s protein molecules cannot be repaired and will cause off-flavoring.
To study whether heat is a factor in denaturing egg white, researchers used a vertical flat-sheet polyacrylamide gel electrophoretic method and differential scanning calorimetry to analyze the changes in the egg whites. They found that heating egg whites made them more unstable to heat, and ovotransferrin was the most sensitive. Other proteins, including ovomucoid and ovoinhibitor, did not aggregate in egg whites despite high levels of acidity.
Heat and alcohol affect protein shape. When exposed to too much heat, or acid, weak hydrogen bonds break. The hidden parts of the protein structure become exposed and form bonds with other molecules. They are then insoluble in water. In some cases, heat and alcohol can restore the original structure. This process is called renaturation. If the eggs are heated, it makes the protein insoluble. This process can also cause it to lose its color.
The egg white is composed of 40 different kinds of proteins. The major ones are ovalbumin, ovotransferrin, and ovomucoid. Ovomucoid contains a flavoprotein that binds riboflavin and biotin. Avidin and lysozyme are proteins that have a lytic effect on bacteria.
In this study, we investigated the electrochemical reactions that occurred when eggs were heated. The oxidation process involved electron transfer between the anode and iodide ions. Iodine cations are small enough to enter the inside of proteins and possess a moderate reactivity toward thiol groups. These properties may be beneficial in oxidizing buried residues. Our results showed that oxidized egg white proteins contained ovalbumin monomers.
In addition to this physical process, eggs are also characterized by their unique color. Eggs’ unique color is caused by the chemical reaction of their protein molecules. Egg white proteins are tightly folded in the water at room temperature, and when heated, they uncoil, forming a web of interlinked protein molecules. This tangled web traps water molecules and alters the color of the egg. This reaction is known as coagulation, and the higher the temperature, the more eggs change color and texture.
Another effect of the electrochemical reaction on egg white was seen in pidan. The colour may be due to a process called a Maillard reaction. In contrast, the glucose-induced liquefaction results in the formation of a gel-like structure in egg white. However, the effect of this process depends on the type of cation that is used. Glucose, which accounts for approximately 0.4% of the egg white, can be used to create gel-like substances.
This process involves the use of electricity to heat food and process them. In this context, understanding the impact of ohmic heating on the quality and safety of food is essential. There are several factors that affect electrical conductivity in food. Free water and ionic strength are important factors. Generally, foods that contain ionic substances will increase their electrical conductivity while those containing non-polar constituents will decrease it.
Hydrogen sulfide produced
You may have heard of hydrogen sulfide, the sulfur gas produced when cooking a boiled egg. Egg whites are proteins that contain a small amount of sulfur, which reacts with the hydrogen to form hydrogen sulfide. The result is a noxious, foul-smelling gas. If you’re a chemistry major, you’ve probably heard about the smell of hydrogen sulfide. But what is hydrogen sulfide?
The hydrogen sulfide gas that’s produced during the heating of an egg reacts with the iron in the yolk to produce a green layer. This layer can be easily avoided by cooling the egg as soon as you finish cooking it. Ideally, an egg should be room temperature or slightly warmer. However, if the temperature of your egg is too low, hydrogen sulfide will migrate to the yolk and react with the iron in the yolk, producing the green rim.
This gas is also known as sewer gas. It is a flammable gas with an odor similar to rotten eggs. While it doesn’t make you sick at low levels, exposure to it can cause olfactory fatigue. Even though the gas is not toxic at normal levels, it can be hazardous if you’re working around it. It can accumulate in low-lying areas and in enclosed spaces, so it’s best to avoid contact with it.
One way to prevent hydrogen sulfide production is to use electrochemical oxidation. This process oxidizes thiol groups in protein and suppresses the formation of hydrogen sulfide. Another way to reduce the hydrogen sulfide content of egg white is to heat it to a lower temperature. By heating it to a lower temperature, the hydrogen sulfide level decreases, while the protein remains intact and functional.
You can also avoid exposure to hydrogen sulfide by taking precautions when cooking eggs. It is a natural gas found in low-lying areas, but its presence at the home or workplace can be hazardous. If your sewer drain has dry traps, it could leak hydrogen sulfide into your home. It’s also possible to work near areas where hydrogen sulfide is produced.
Effect of beating sugar/egg white mixture on egg whites
To make the best whipped cream, beat a spoonful of sugar into a bowl of egg whites. The sugar acts as a stabilizer, allowing the egg whites to hold up better when heated. Sugar granules dissolved in the water present in the egg whites increase the elasticity of the emulsion. Sugar is hygroscopic, so it prevents water from sinking to the bottom of the whipped mixture. The amount of sugar you add will depend on the recipe you’re making.
Begin beating the egg whites by placing them in a stainless steel or copper bowl. Add a pinch of cream of tartar and beat the mixture slowly. Once it reaches soft peaks, lift the beater and allow the egg whites to curl up. The whipped egg whites should hold their peak and curl slightly at the tip. If you are looking for a stiff peaks, continue beating the mixture until it reaches stiff peaks.
To understand the process of foam formation, you must understand how proteins work. Water molecules are attracted to the hydrophilic ends of the protein and squeeze out the hydrophobic ends. The end product of this process is foam. When this happens, the protein molecules become trapped between the water and air bubbles, creating a network that is tough and dry. In other words, when egg whites are overbeaten, they tend to dry out and lose their fluffy texture.
The sugar used to create foam in egg whites is called superfine sugar. Superfine sugar will dissolve more quickly. Be sure to add the sugar gradually, as it will reduce the volume of the egg whites. Also, use a medium-sized bowl with straight sides. Begin beating the egg whites at low-speed and continue until the foam reaches its peak. This will make the foam stable.
Adding cream of tartar to the egg white mixture will stabilize the beaten eggs. When the mixture is at room temperature, it will whip better and foam up to 6 to 8 times its original volume. Add more sugar when the whites reach the soft peak stage. Adding sugar gradually will create a soft peak. A soft peak is achieved after 30 minutes. When whipped, egg whites will reach six to eight times their original volume.
About The Author
Gauthier Daniau is a freelance problem solver. He first discovered his knack for trouble-shooting when he was still in diapers - and hasn't looked back since. When he's not slaying zombies or internet ninjas, GAUTHIER enjoys working with animals of all shapes and sizes. He's also something of a social media expert and loves to get lost in numbers and figures.