Microwaves are a blessing! From college students to working families who can't afford to spend hours preparing a meal, the sheer amount of time microwaves can save makes them well worthwhile. However, as awesome as it can be to revive cold foods in the microwave, it may not be the best idea for certain foods – of which potatoes and eggs are chief. Potatoes and eggs have a funny habit of imitating fireworks when microwaved. Although they both explode when exposed to microwave heat, the mechanisms of explosion are far from the same.
Although most YouTube folks detonate eggs in the microwave just for fun, there is a science behind it. Egg yolks contain about 50% water and it is now believed that this water is trapped in small pockets within the protein matrix. So, when eggs are heated in the microwave, these water pockets super-heat – way above the normal boiling temperature, leading to a very unstable condition. At this point, any disturbing stimulus applied to the egg (be it a poke with a knife or an unfortunate bite from a hungry man,) will inevitably lead to a spontaneous boiling of the water pockets, a.k.a., an explosion!
Exploding eggs generate a peak sound pressure ranging from 86 to 133 decibels at one foot away. Although loud, it is not sufficient to cause hearing damage – as claimed by a plaintiff in a case where he stated that a microwaved egg exploded in his mouth at a restaurant and caused severe burns and hearing damage.
The applications of this study extend beyond proper warnings by microwave manufacturers but will also help in enhancing our understanding of impulsive sound sources that can lead to hearing damage. More details about this study were published in the abstract of the paper by Anthony Nash and Lauren von Blohn, which was later presented by the authors at the 174th Meeting of the Acoustical Society of America, held on December 4-8, 2017, in Louisiana.
For more food-related engineering, check out Adding Up the Perfect Cup.