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  Why do bananas get bruised as they age?

   
  Bananas
   
  Why do bananas get bruised as they age?

Liken the black spots on bananas to the liver spots on mature adult, they appear with age, even if they go untouched. The hormone ethylene, a ripening agent found in the skin of the banana, transforms a green banana into the appealing yellow fruit we purchase at the market.

Ethylene, however, continues the ripening process, which gives the banana a "bruised" appearance, and eventually turns the banana black in color. There is no switch to turn off this process, but by placing the banana in a cool place, one can slow the process. The refrigerator is no place for a banana, because this is certain to blacken it prematurely. The cold air, to which the banana is exposed, causes the production of blackening compounds known as polyphenols.

Did you know?

In North America more bananas are eaten every day than any other fruit.

Bananas aren't grown on trees. They're part of the lily family, a cousin of the orchid, nothing but a very yellow and plump member of the herb family. With stalks 25 feet high, they're the largest plant on earth without a woody stem.

The word banana is African, though, a word carried to the New World by Portuguese slave traders. In Alexander the Great's time, bananas were called "pala" in Athens.

North America got its first taste of the tropical fruit in 1876 at the Philadelphia Centennial Exhibition. Each banana was wrapped in foil and sold for 10 cents.

 

note:


hormone
: 荷爾蒙
ethylene: 乙烯
ripening agent: 催熟劑

 

 

 

 


polyphenol: 多酚

 

 


lily family: 百合科
orchid: 蘭花

 
 
 
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