The eggs salted in a brine solution containing a higher salt concentration have a higher salt content in the egg white, which dissociates the structure of the ovomucin and causes the egg white to thin and decreases the ovomucin level, leading to an increased pH value in the egg white.
Salt decreases egg-white foam stability, so it is not used in meringues. Add sugar gradually. For optimum volume and smoothest texture, sugar should be added gradually, beginning only after the whites have been beaten to the foamy stage (about double in volume).
Beat your egg whites with a pinch of salt. And do it with an electric mixer. The salt helps to tighten te texture of beaten eggs, and the electric mixer is better to perform this action quickly. Also make sure to clean the bowl.
Salt and acids (like vinegar) can also denature proteins in the same way heat does. Adding these substances speeds up the process by which the egg whites solidify and stops the seepage. In fact, some recipes call for eggs to be hard-boiled in vinegar and salt water to prevent the leaks from ever occurring.
The salt allows the egg whites to incorporate more air while being beaten. Poached or fried whole eggs toughen when salt is added before cooking, but when a small amount of salt is added to scrambled eggs or omelets the albumen in the egg white breaks down faster and makes blending with the yolks easier.
As J. Kenji López-Alt explains in his book The Food Lab, salt inhibits the proteins in the egg yolks from binding too tightly as they heat up, which results in a moister, more tender curd: “When eggs cook and coagulate,” he writes, "the proteins in the yolks pull tighter and tighter together as they get hotter.
Pepsin, which is secreted by the cells that line the stomach, dismantles the protein chains into smaller and smaller fragments. Egg proteins are large globular molecules and their chemical breakdown requires time and mixing.
The protease enzyme acts to cut up the egg white proteins making the fragments soluble, so they just dissolve. The egg white is made up of proteins so will be broken up by a washing powder with enzymes to break up proteins (proteases).
At what temperature does egg white denature? Egg white has many different proteins, but the bulk (54%) is a protein called ovalbumin which denatures at 184F. That's a temperature you easily hit during cooking (remember water boils at 212F approximately).
New, room temperature egg whites will whisk up faster than old, cold eggs. Make sure the bowl you whisk the egg whites in is free from any greasy residue. Make sure that no egg yolk is in with the egg whites. Egg yolks are very high in fat and will hinder the whisking process.
For stable egg whites that will never get out of hand, just add a little acid. Acid prevents certain components of the egg proteins from bonding together too tightly, which can lead to a foam that separates into a mass of sad bubbles and a runny liquid. My favorite acidic ingredient for this is cream of tartar.
Adding in sugar has many benefits. Sugar pulls the water from the structure and allows it to hold its shape better; egg whites beaten without sugar will not peak as firmly as those with. Beaten whites can also sit and hold their shape longer than foams without sugar.
Acid (lemon juice, vinegar, tartar powder) stabilizes the cross-linking of the proteins; the egg white mass becomes firmer. Even small amounts of egg yolk or fat can prevent stiffening.
Adding some form of acid, like white vinegar or lemon juice can also add stability to your egg whites. In general, about 1/8 tsp. of vinegar or lemon juice per egg white added during the foaming stage is enough!
"To kill salmonella you have to cook eggs to 160 degrees Fahrenheit," she wrote. "At that temperature they are no longer runny."
Cooking (hot water).
As heat denatured the proteins in the egg white, it broke apart some of the bonds (mostly hydrogen bonds) that were holding the proteins in their original shape. The proteins unfolded, taking up more space (turning the gel white) and hardening them in place next to one another.
The principal proteins in egg white are albumen (water soluble) and globular proteins (soluble in neutral dilute salt solutions). To aid solubility of egg white, addition of small amounts of sodium chloride is a common practice.
The salt in the water will help with egg flavor since the eggs will absorb some of the salt while cooking. Additionally, some people swear by salt for easier egg peeling.
This membrane is 'selectively permeable' which means it will let some things through but not others. An egg's membrane will allow small molecules like water to pass through, but not large ones like salt. The egg left in water looked very different to the one in salt water due to a process called osmosis.
By contrast, when an egg is treated with distilled water, or a dilute salt solution, the solute concentration is higher inside the egg than out, so the water moves into the egg, increasing its mass. It may be easier to think about osmosis in terms of water concentration rather than solute concentration.
The salty water is absorbed through the shell of the egg and flavours the egg to make these amazing salted duck eggs.
The sugar is added once the egg whites have been whisked until they are at the point where they form satiny peaks, as with most meringue mixtures. If the meringue mixture becomes flat or runny when the sugar is added then it usually means that the egg whites were not quite whisked enough before the sugar was added.