Secret behind the popping corn??

 

Secret behind the popping corn??

Every time I eat popcorn, there is question arises in my mind that how the hell is corn popping inside and volume expands 40-50 times of the kernel size.

Does this question not come in your mind? I am sure you have. So let’s see what’s happen during the process of corn.

There are so many varieties of corn which you have seen and eaten in your life. The popcorn is a special variety of corn which is most suitable for the popping corn.

(pic source- google image)

Three things which leads to popping corn when its put on the heating pan

•        Moisture trapped in the corn
•        Starches inside in the corn
•        Outer hard layer of corn.

The popcorn is the funniest food to prepare because it jumps and make pop sound when you put on the heated pots. These three factors work together to bring the corn in popping state, which is 40-50 times larger than the original corn kernel. Generally, the cereals store at lower moisture content about 12-14% (wet basis) and the intracellular moisture content in the pericarp layer of the corn. When corn put on the heating pan up to 180-190⁰ Celsius the moisture inside the corn get vaporized and exert pressure on the outer layer of the corn. Along with the starch get gelatinized within the corn and expands so both the generated pressure and starch mass try to escape out of the layer and when the outer layer doesn’t bear the maximum pressure it gets burst and pop out of the corn.This seems very simple when you tell, but behind this scene there is lot of reaction occur to reach the optimum popped corn state.

 

Warm up heating period-

It is the period when the popcorn put inside the pan or oven to pop where the temperature increasing rapidly and moisture inside get vaporized up to 100 Celsius and the starch gelatinized and make whipped structure (colour from white to creamish white) and even the built up pressure is not enough to explode the corn so further heating is done and the temperature range betwenn 177-187 Celsius most of the popcorn explodes.

 

 

 

Jumping of the popcorn-

The explode of the corn makes it jump inside the pan, the popcorn jump is matter of debatable but still there are finding which suggest the corn makes itself jump like an acrobat jump on 360 angle and land on the land. The heating up to 180 Celsius makes changes inside the corn kernel. Before the explode there are stages which ultimately leads to the explosion of the kernel. The gradual heating increases the pressure inside of the corn and starches gelatinized expand and put force on the outer layer of the corn and it is starts fracture on the surface of the kernel which sets it ready for the take of  for the jump and when it finally reached the stage at which the it explodes the force and the gelatinized mass push it upward and makes it jump high (in open pan).

 

Pop sound-

If you paid attention  there is sound upon the popping of the corn which is quite mystery till date. But extensive research finds the theory behind the popping sound of the corn is the pressure built up inside makes cavity inside the corn and when it explodes the sound come, other thought on the popping sound may be due to the crackling fracture of the corn or the pressure release on the explosion, but both doesn’t support the experimental data found by the researches.

 

 

 

Reference-

 If you want to go deeper and understand the mechanism scientifically please go through the artilce below linked.

1.    Virot, Emmanuel, and Alexandre Ponomarenko. “Popcorn: critical temperature, jump and sound.” Journal of the Royal Society, Interface vol. 12,104 (2015): 20141247. doi:10.1098/rsif.2014.1247 (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4345489/

Images credit- images are taken from the article Popcorn: critical temperature, jump and sound.” Journal of the Royal Society, Interface vol. 12,104 (2015): 20141247.