«He cannot even boil an egg!» complains sometimes a wife while talking to her husband, as if boiling an egg were the easiest thing in the world, but boiling an egg doesn’t mean low culinary skill: cooking an egg in water is less simple than what it seems.
An egg is 74% water, 12% proteins and 11% fat with traces of vitamins, minerals and other substances.
And its proteins, thanks to their ability of coagulating with increasing temperature, allow us to prepare a boiled egg.
By increasing the temperature some proteins are denatured.
When two denatured proteins meet each other they can bind together, forming a solid three-dimensional network that traps the water molecules within it: this is the coagulation of proteins.
If the cooking is not performed according to the correct parameters, the protein network can become too thick: the texture of the egg white becomes slightly chewy and not tasty, while the yolk becomes dry and almost sandy.
But let’s go to the details.
At 100 °C the egg white and the yolk coagulate both, but since the yolk needs more time to be cooked, because it is more interior, the egg white may be overcooked.
So it’s easy to understand that the secret of a perfect egg is not the time but the temperature.
A perfect cooking should always follow the coagulation temperature of the proteins, which is always lower than 100 °C.
There are several proteins in the egg and each of them coagulates at different temperatures (the ovotransferrin at 62 °C, while the ovalbumin at 85 °C).
However, since the ovotransferrin is only 12% of egg white proteins, it remains soft. The ovalbumin, which instead represents 54% of egg white proteins, when it coagulates, the egg white becomes more compact.
The egg yolk instead thickens at 65 °C and solidifies at 70 °C.
Getting the perfect textures of an egg is one of the biggest challenges even for the best restaurants because of its delicacy: eggs need an extreme care, that no other food requires.
For example by cooking an egg at 65 °C, only one of the proteins in the egg whites coagulates and the egg white becomes incredibly soft. The yolk is no longer liquid, but creamy!
If you cook an egg at 64 or 69 °C and taste its textures, it is easy to notice the differences between the two preparations.
You will notice that two degrees more or two less change the texture of the yolk and egg white.
The temperature is the true guide of every preparation, the only one which is responsible for the outcome of a perfect dish.
For example, by exceeding the egg cooking, you get a chewy texture of the egg white, and the yolk becomes dry and granular.
Furthermore, it could also form a gray-greenish film around the yolk, because a little of dihydrogen sulfide is developed (H2S) in the egg white (the gas that smells just like rotten eggs!)
Then because of the iron in the yolk, iron sulfide is formed: this greenish and very unaesthetic colour is very feared by cooks because it greatly affects the presentation of the dish.
Well, surely not the result we want! And even our customers and guests too!
For this reason, we want to give the right importance to the temperature for what it does in every preparation in the kitchen because it is the only one that guarantees the success of a dish.
The best result is strictly linked to a precise temperature control, UP TO THE SINGLE DEGREE!
By learning to master the temperature, all the uncertainties about the future repeatability of the wonderful dishes you have created will automatically disappear and your customers will thank you forever!
For a truly PROFESSIONAL result, HotmixPRO gives you the amazing possibility to master the temperature,
through the DEGREE BY DEGREE CONTROL!
No more approximations! Now you can really achieve perfection thanks to a professional precision!
This article is based on the information in the «L’uovo a 65 gradi» published in Le Scienze Blog
For more details HERE is the full article in italian
Credit: Dario Bressanini