Science Behind It: Why Do You Cry When Cutting Onions?

You grab the onion, slice it, suddenly – bam! Your eyes start to sting and the water flows down your cheeks, feeling like you’re crying on a chopping board. But you are not sad – just cooking. This is a shared kitchen experience around the world. But you’ve stopped to know Why Onions make us cry? In all the vegetables we chop, why does onions have this tearing effect?

Onions are a staple food in the world. They add depth, aroma and sweetness to the dishes, but also have a tingling sensation in the text. The science behind this tear reaction is fascinating and rooted in the natural chemistry of onions and its clever defense mechanisms. Let’s take a closer look at the real reason behind the tears.

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Why does cutting onions make you cry?

To understand why onions trigger tears, we need to start with what happens inside the onions. These plants have evolved chemical defenses to protect themselves from pests and predators.

1. Onion’s natural defense system

Inside an onion, separate two key components in a separate compartment of its cells:

When the onions are intact, these compounds remain safe to separate. However, once the layer is cut open, the cells are ruptured and their contents are released.

So when you slice the onion into thin slices, you allow the enzyme to be called adenases and a group of sulfur-containing compounds called sulfur oxides (specifically, S-1-Phenylbenyl L-cysteine ​​sulfur dioxide). When the two ingredients are mixed, they react to form sulfuric acid.

2. Input tear gas: Synthesis – Methyl oxide

Sulfuric acid is unstable, so it quickly re-exhausts it into a volatile gas called Cert-S-oxide. This compound is a true tear inducer. This is a lachrymatory factor, which means it stimulates the eyes to produce tears.

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Once released into the air, it bends upwards and comes into contact with the surface of your eyes. Your eyes find it irritating and the lacrimal glands stick into the gears to flush them off, so they cry.

The feeling of burning or tingling is the result of the interaction of acid with the nerve ends in the eyes. This is similar to how pepper spray works, although luckily, it’s hardly that intense. Your tear glands enter the speeding drive that tries to protect your eyes, causing those familiar tears to flow down your cheeks.

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Why are there only onions?

Onions belong to onion Family, which also includes garlic, leeks and scallions. Other members of the Allium family contain similar sulfur compounds, but onions contain higher concentrations, especially those grown underground. For example, garlic has different types of sulfur reactions, which affects taste and smell more than tear ducts.

Interestingly, different onion varieties produce different levels of tear gas. Sweet onions have less sulfur. Sweet varieties such as Vidalia or onions cause fewer tears. While yellow, white and red onions are more irritating, have higher sulfur levels and are more likely to trigger a crying session.

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Can you prevent it?

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Yes! Here are some scientifically supported tips that can reduce the tearing effect of cutting onions:

• Cool the onion before cutting: Cooling slows down the enzyme and reduces the amount of gas released.

• Use a sharp knife: Clean cutting will cause less cell damage, thereby reducing the release of sulfur compounds.

• Cut near running water or fan: This will spread the gas before it reaches the eye.

• Wearing goggles: It looks stupid, but it can be used.

in conclusion

So the next time you chop the onions and your eyes start watering, remember – not you, it’s a chemistry. The humble onion defends itself through a mini chemical war, which activates the moment the knife hits the surface. But now that you know the science behind it, you can take steps to go beyond it, or at least understand why you are crying on chopped onions.

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Source: https://dinhtienhoang.edu.vn
Category: Optical Illusion