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  • Sometimes when I'm chopping onions I just get allTEARY WOW. WHAT THE HELL'S GOING

  • ON HERE.

  • When I chop onions it's a constant battle to not feel like I just watched the 1995 classic

  • A Little Princess. My eyes well up with tears and it HURTS. You know? What's going on? What

  • is this witchcraft?!

  • Well, to be honest, you're doing it to yourself. Your tears reacting with a chemical released

  • by the onion which creates an acid IN your EYE!! SO CRAZY.

  • Okay, so, onions are a delicious root vegetable member of the genus Allium, along with garlic,

  • leeks, chives, shallots, and some 400 other species,. When you plant something, it doesn't

  • just suck up water and sunlight; it also needs nutrients from the soil. Good soil contains

  • organic matter that the plant can absorb like nitrogen, phosphorous, carbon, AND sulfur

  • -- which this bulbous fleshy vegetable tends to absorb a lot of!

  • When you cut open an onion you're breaking apart its cell structure allowing amino acid

  • sulfoxides to form sulfenic acid. It also releases the enzyme lachrymatory-factor synthase

  • which reacts with that sulfenic acid to form an airborne volatile chemical called propanethiol

  • s-oxide. As that chemical rises into the air it eventually meets the tears already present

  • in your eyes.

  • There are three types of tears, emotional or psychic tears that we cry when we're sad;

  • basal tears which are constantly replenished to keep our eyes lubricated; and reflexive

  • tears which flush the eye in response to an irritant -- like ACID. Tears contain water,

  • mucus, oil, nutrients for eye cells, and antibacterial lysozymes. When propanethiol s-oxide hits

  • that water, it rearranges YET AGAIN, forming sulfuric acid -- battery acid! IN YOUR EYES!

  • So, you cry when an onion is cut because enzymes create battery acid in your eyes. Just another

  • day for nature. The more I learn about the world, the less I feel like I actually know

  • about anything.

  • I know what you're thinking, "Why don't we just breed this nightmare ingredient out of

  • onions?! We can make seedless fruit, why not tearless onion? Well, you can refrigerate

  • the onion to slow down the chemical reaction and reduce crying, but getting rid of it altogether

  • would involve breeding it out, and previous studies of onion biology concluded the onion's

  • flavor AND the acid reaction was thought to come, in part, from the enzyme alliinase.

  • Breed out the alliinase and the onion wouldn't taste likewellan onion. Then in 2002,

  • a study in Nature found that may not be true at all! Instead, they believe there's a quote

  • "yet undiscovered enzyme," at work here. That's right. Onions are confounding science. to

  • Maybe we could breed onions that have less of that mystery enzyme, maintain the flavor

  • and not get red and puffy, but we don't

  • know yet.

Sometimes when I'm chopping onions I just get allTEARY WOW. WHAT THE HELL'S GOING

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洋蔥為什麼會讓你哭? (Why Do Onions Make You Cry?)

  • 105 11
    Jack 發佈於 2021 年 01 月 14 日
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