Scientists Reveal the Mystery behind Cooking Popcorn

April 21, 2015

Unlocking Word Meanings
 今日の単語・フレーズ

Read the following words/expressions found in today’s article. 

1. phenomenon /fɪˈnɒm əˌnɒn/ (n.) – an observable event or fact
Example: Lightning is a natural phenomenon.

2. unveil /ʌnˈveɪl/ (v.) – to reveal or expose something
Example: The experts unveiled the mystery behind the black hole.

3. minuscule /ˈmɪn əˌskyul/ (adj.) – referring to something that is very small
Example: There is a minuscule amount of blood in his urine.

4. innards /ˈɪn ərdz/ (n.) – the internal parts of something
Example: The biology students checked the innards of the frog.

5. instantaneous / ˌɪn stənˈteɪ ni əs / (adj.) – referring to something that happens very quickly
Example: The water had an instantaneous change in temperature.


Article
 ニュース記事

Read the text below.
Through a study, some physicists were able to unveil the phenomenon behind cooking popcorn.

The history of popcorn dates as far back as the 16th century. Back then, it was used as part of Aztec Indian ceremonies. Now, this food product has become a very common snack often associated with watching a movie. It has become very popular that an average American citizen actually eats around 51 quarts of popcorn annually. 

Despite popcorn’s popularity, not much is known why its kernels are able to pop the way they do when being cooked. To gain knowledge about this phenomenon, French physicists Emmanuel Virot and Alexandre Ponomarenko observed the popping process of the product. They used a special high-speed camera to record the popcorn’s activity while inside a heated oven.

Results showed that a popcorn kernel has a minuscule amount of moisture inside it. At 100 °C, this moisture turns into steam. Upon reaching 180°C, the water vapor tries to escape, thus forcing the innards to expand and break through the kernel’s shell.

Aside from the popping process, the physicists also studied the way the popcorn jumps. During their observation, they noted that the first thing to come out of the shell was a small portion of the popcorn, which they call “leg.” The energy released into this leg allows the kernel to push against the hot surface, making it jump a few millimeters to centimeters.

Lastly, the scientists found that the popcorn’s popping sound is caused by the instantaneous release of the trapped water vapor inside the kernel.

Viewpoint Discussion
 ディスカッションテーマ

Enjoy a discussion with your tutor.  

Discussion A

·         What part about how popcorn cooks did you find most interesting? Kindly discuss your answer.
·         Why do you think the researchers chose to study about popcorn?

Discussion B

·         If you were a scientist, what experiment would you conduct? Kindly discuss.
·         What other phenomena do you think scientists should research on? Please explain your answer.

April 21, 2015