The art of cooking an egg actually consist of nothing more than introducing heat energy into it to such an extend, and at a high enough rate, so that – from a culinary perspective – both the yolk and the egg white will have undergone precisely the desired changes. However, we all know from experience that boiling the breakfast egg to perfection can be far from child’s play.
The egg yolk sets at lower temperature than the egg white. For a soft-boild egg, the yolk temperature should not exceed 65 °C.
Many egg boiling instructions create a formula for a given egg such as: put egg in cold water, bring to boil, boil for 4 minutes. However, many factors effect the cooking time of an egg:
- egg size
- surrounding pressure
- surrounding temperature
- initial egg temperature
- heat retention of the pot
- heat output of the stove
So how to figure out when to stop the cooking?
Probably there is no eays answer. However, chemists like to experiment … In this regard, Hans Bauer and Klaus Roth came up with the first non-invasive method for culinary evaluation of soft-boiled eggs in a truly reliable way. Analysis takes only 3–4 minutes, you would only need quite some space in your house, and ca. 2 million euros … (check out methode)
Last but not least, after boiling quickly transfer the egg to cold water to prevent their cooking further.
How much do you know about eggs and their chemistry? Easter Egg Trivia quiz
During boiling individual proteins lose their organized spatial structure, without any bonds being broken between the various amino acid components. This is a result of denaturation. Through aggregation, various proteins gather together, with the resulting aggregates being maintained through hydrogen bonds, disulfide bridges, and an assortment of ionic and hydrophobic interactions. Coagulation leads to random clustering of proteins that have already succumbed to denaturing.
Find the above and much more information around the boiled egg in: Boiled Eggs: Soft and Hard
by Klaus Roth, ChemViews Mag. 2012. DOI: 10.1002/chemv.201200018