Microwave ovens are often a quick way to heat food and have become a basic kitchen appliance in both domestic kitchens and restaurants. If you have carefully observed the warnings of the microwave or if you have experienced an accidental explosion, you know that certain foods present a risk due to an increase in internal pressure. Potatoes and boiled eggs are some of the most common culprits of potentially dangerous explosions. Although potatoes and eggs can explode, their mechanisms of explosion are different.
Anthony Nash and Lauren von Blohn, of Charles M. Salter Associates, will present their research on the acoustic pressures generated by the explosion of eggs at the 174th Meeting of the Acoustic Society of America, to be held from December 4 to 8 of 2017, in New Orleans, Louisiana.
Nash and von Blohn explored the mechanism of egg bursting as part of the testimony of an expert witness for litigation where the plaintiff allegedly suffered severe burns and hearing damage in a restaurant after he hatched a hard boiled egg in his egg microwave. mouth.
"We needed to quantify the maximum sound pressures of an exploding egg to be able to compare it with the risk criteria for hearing damage," Nash said. "At a distance, the maximum sound pressure levels of microwaved eggs covered a wide range of 86 to 133 decibels, only 30% of the eggs tested survived the microwave heating cycle and exploded when drilled with a sharp object., the probability of an egg exploding and damaging the hearing is quite remote, it's a bit like playing egg roulette. "
Because there was little scientific literature on the subject, the researchers initially took an unorthodox approach when reviewing the YouTube collection of microwave explosions.
"Those experiments had been performed by non-scientists who casually detonated eggs in a microwave," Nash said. Since their experiments seemed to be more for personal entertainment than for scientific exploration, they did not control a number of important variables, including measuring sound levels or internal temperatures, or documenting the various types and sizes of eggs.
For the Nash and von Blohn experiments they explained these variables, which were very controlled. First, selected hard boiled eggs were placed in a water bath and heated for three minutes, and then the water bath temperature was measured both in the middle and at the end of the heating cycle. Finally, the eggs were removed from the water bath, placed on the ground and pierced with a fast-acting meat thermometer to induce an explosion.
"For eggs and eggs that did not explode, we would probe the inside of the yolk with the thermometer," Nash said. "We found that the temperature of the yolk was consistently higher than the surrounding water bath."
The implication is that the egg yolk is more receptive to microwave radiation than pure water (water makes up about half the weight of the egg yolk). The duo hypothesized that the egg's protein matrix traps small pockets of water inside the yolk, causing the bags to overheat well above the nominal boiling temperature of the common tap water. When these overheated pockets are disturbed by a penetrating device, or if one attempts to bite the yolk, the pockets of water boil in a furious chain reaction that leads to a phenomenon similar to an explosion.
The applications of this research may extend beyond the obvious warnings of microwave oven manufacturers and contribute to the growing understanding of impulsive sound sources that cause hearing damage.
Eggs without yolk can also hatch
Summary: 3aAA11: "Sound pressures generated when eggs explode," by Anthony Nash and Lauren von Blohn, December 6, 2017 at Studio 9 at the New Orleans Marriott. asa2017fall.abstractcentral.com/s/u/3Cw0kpJV_I4