Scientists explain why grapes "ignite" in microwaves and produce plasma

In 2011, impressive videos of split the grapes that burned when cooking in the microwave became viral on Youtube. What was happening? Nobody knew, but now the phenomenon has finally been received! a physical explanation The scientists responsible for the discovery of the mystery are Hamza Khattak, Aaron Slepkov and an Argentine, Pablo Bianucci.

In an article published in Proceedings of the National Academy of Sciences, researchers from University of Trento, from Canada, stated that the fireball is not the result of heat from the outside of the grapes, but that occurs because of hot spots that form on both sides of the fruit.

In viral videos, it was enough to cut a grape in half, to leave the two halves connected by a little skin at the bottom and to heat them in the microwave oven. in a few seconds, a small fireball would appear between them. The strange thing was that no one could explain why it had happened.

Since then, many scientists have presented possible explanations. One of the most popular was the suggestion that grapes somehow form an antenna that directs the microwaves through the skin bond. In this new effort, physicists have performed several tests on fruits and other similar objects to discover the real reason from the formation of the fireball.

The tests consisted mainly of using thermal cameras to capture the action because the grapes were heated and simulated. They also tried plastic balls and fruits of similar size filled with water.

The researchers discovered that the formation of the fireball resulted from a simple process. As microwaves enter the grapes, hot spots are formed on the two pieces at the points where they are closest to each other because of a link between them. As the hot spots get hotter, the surrounding electrolytes become overloaded, resulting in the formation of a plasma explosion in the form of a small fireball.

Physicists have pointed out that The same effect could be produced with fruits of similar size or balls filled with water. They also found that it was not necessary to maintain any type of physical connection between the two rooms; all that is needed is that they are not separated by more than three millimeters.

Veritasium's YouTube channel has been maintained with two of the three scientists responsible for this discovery. The video, in a few days, already accumulates more than two million views. People are interested in science! Here you can see it, but it's in English.