The popcorn I ate when I was a child was very loud. Why is it not so loud now?

The fragrance of rice flowers bears the happiness of many people's childhood. Most children living in rural areas have this experience when they were young, and they heard "Bang! Bang! Hey! " Noisy, or hear the cry of the uncle who makes popcorn, ask mom for a bag of corn or rice and run out to find the location of popcorn.

Rubbing hands with a group of friends and waiting for the popcorn in the pot to heat up, uncle said "covering his ears" and waited for the loud noise. How many people were scared by that black boiler? The official name of this old popcorn machine is actually "gunner popcorn machine" Now we can't see this popcorn machine in the city, and we can only find its trace in some museums or remote mountainous areas. But this old-fashioned popcorn machine was not invented by China, but by the British in the late19th century, so it is also called English popcorn machine.

Only in the 20th century, in the era of electrification, this popcorn machine was retired in western countries, but it became a childhood memory of China generation. The working principle of this popcorn machine is to change the pressure inside the machine. Due to heating, the pressure inside the machine rises slowly. When people open the cover of the machine, the high temperature and high pressure inside the machine erupt with the processing raw materials, and the external pressure drops rapidly. The gas inside the corn grains expands rapidly and the corn grains become popcorn. So this handheld popcorn machine has become something that many people love and hate in their childhood. What they love is that it can make corn, rice, yellow rice and broad beans into crispy rice flowers and add a handful of sugar, which is a delicious snack. What I hate is the loud noise at the moment when the cover was lifted, which made many people jump up in fear and appease their pounding hearts. However, this loud noise stopped in many people's childhood. Now, a new type of popcorn machine is born, and the loud noise of childhood gradually recedes with the handheld popcorn machine.

Why doesn't the new popcorn machine make such a loud noise now? The popcorn we eat now is completely different from the popcorn made from a bag of corn at home before. Our own popcorn is common edible corn, which needs to be exploded under high temperature and high pressure, so we need to hold popcorn to give corn a high pressure environment. Now the popcorn sold in the cinema is American popcorn, and the corn used is special small popcorn. This kind of corn originated in the United States, with small particles and hard skin, and its water content is about 14%. This kind of popcorn has a low temperature and does not need a high pressure environment. It only needs simple heating to make corn swell and break into popcorn. The produced popcorn is whiter, softer in taste and better in quality.