美女视频黄频大全视频

Why Do Onions Make You Cry?

iStock/D-Keine
iStock/D-Keine

美女视频黄频大全视频The has been traced back as far as the Bronze Age and was worshipped by the Ancient Egyptians (and eaten by the Israelites during their bondage in Egypt). Onions were rubbed over the muscles of Roman gladiators, used to pay rent in the Middle Ages, and eventually brought to the Americas, where today we fry, caramelize, pickle, grill, and generally enjoy them.

Many of us burst into tears when we cut into one, too. It's the price we pay for onion-y goodness. Here's a play-by-play breakdown of how we go from grabbing a knife to crying like a baby:

1.美女视频黄频大全视频 When you cut into an onion, its ruptured cells all sorts of goodies, like allinase enzymes and amino acid sulfoxides. The former breaks the latter down into sulfenic acids.

2. The sulfenic acids, unstable bunch that they are, spontaneously rearrange into thiosulfinates, which produce a pungent odor and at one time got the blame for our tears. The acids are also converted by the LF-synthase enzyme into a gas called syn-propanethial-S-oxide, also known as the lachrymatory factor (or the crying factor).

3.美女视频黄频大全视频 Syn-propanethial-S-oxide moves through the air and reaches our eyes. The first part of the eye it meets, the cornea, is populated by autonomic motor fibers that lead to the lachrymal glands. When syn-propanethial-S-oxide is detected, all the fibers in the cornea start firing and tell the lachrymal glands to wash the irritant away.

4. Our eyes automatically start blinking and producing tears, which flushes the irritant away. Of course, our reaction to burning eyes is often to rub them, which only makes things worse since our hands also have some syn-propanethial-S-oxide on them.

It only takes about 30 seconds to start crying after you make the first cut; that's the time needed for syn-propanethial-S-oxide formation to peak.

WHY DON'T GREEN ONIONS MAKE US CRY?

The onion's relatives, like green onions, shallots, leeks and garlic, also produce sulfenic acids when cut, but they generally have fewer (or no) LF-synthase enzymes and don't produce syn-propanethial-S-oxide.

HOW DO I AVOID CRYING?

Since I usually go through a good deal of onions while cooking at home, I've been road testing some of the different methods the internet suggests for reducing or avoiding the effects of the lachrymatory factor. Here's what I tried:

Method #1: Chill or slightly freeze the onions before cutting, the idea being that this will change the chemical reactions and reduce the gas that is released.
Result: 美女视频黄频大全视频The onion from the fridge has me crying just as quickly as room temperature ones. The one that was in a freezer for 30 minutes leaves me dry-eyed for a bit, but by the time I'm done dicing my eyes start to burn a little.

Method #2: Cut fast! Get the chopping over with before the gas reaches your eyes.
Result: Just hacking away at the onion, I get in the frying pan without so much as a sting in my eyes. The onion looks awful, though. Doing a proper dice, I take a little too long and start tearing up. If you don't mind a mangled onion, this is the way to go.

Method #3: Put a slice of bread in your mouth, and cut the onion with most of the bread sticking out to "catch" the fumes.
Result: It seems the loaf of bread I have has gone stale. I stop the experiment and put bread on my shopping list.

Method #4: Chew gum while chopping. It keeps you breathing through your mouth, which keeps the fumes away from your eyes.
Result: This seems to work pretty well as long as you hold your head in the right position. Leaning toward the cutting board or looking right down at the onion puts your eyes right in the line of fire again.

Method #5: Cut the onions under running water. This prevents the gas from traveling up into the eyes.
Result: An onion in the sink is a hard onion to cut. I think Confucius said that. My leaky Brita filter is spraying me in the face and I'm terrified I'm going to cut myself, but I'm certainly not crying.

Method #6: Wear goggles.
Result: In an effort to maintain my dignity, I try my eyeglasses and sunglasses first. Neither do me any good. The ol' chemistry lab safety glasses make me look silly, but help a little more. I imagine swim goggles would really do the trick, but I don't have any.

Method #7: Change your onion. "Tear free" onions have been developed in the UK via special breeding and in New Zealand via "gene silencing" techniques.
Result: My nearest grocery store, Whole Foods, doesn't sell genetically modified produce or onions from England. Tonight, we eat leeks!

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You Can Win Two Nintendo Switch Consoles While Donating to COVID-19 Relief

Chesnot/Getty Images
Chesnot/Getty Images

Since its debut in March 2017, the Nintendo Switch has been one of the most popular video game consoles on the market, 52 million units worldwide in just three years. But with that type of success comes scarcity—and if you’re looking to pick up your own Switch, well, .

The console has seen supply problems for the past few months due to the coronavirus pandemic, and used and are selling for well over the sticker value online. But with a little luck on your side, you could win two brand-new Switch consoles, thanks to this sweepstakes .

美女视频黄频大全视频Your first entry into the sweepstakes is free, but if you want to increase your chances, you can donate $10 for 100 entries, $25 for 250, $50 for 1000, or $100 for 2000. Those donations will then go International Medical Corps’s Epidemic Response Team—made up of doctors, nurses, and other healthcare professionals—in their worldwide efforts against the coronavirus outbreak. This support includes everything from essential training for healthcare providers and equipment deployment to the administering of medicine and community outreach.

Along with the two Switch consoles, the winner will also receive two Ring Fit Adventure bundles, two Mario Kart wheels, and $600 to spend on more games. The deadline to enter is June 16, with the winner being announced on or around July 1. You can enter for yourself .

At Mental Floss, we only write about the products we love and want to share with our readers, so all products are chosen independently by our editors. Mental Floss has affiliate relationships with certain retailers and may receive a percentage of any sale made from the links on this page. Prices and availability are accurate as of the time of publication.

What's the Difference Between Memorial Day and Veterans Day?

flySnow/iStock via Getty Images
flySnow/iStock via Getty Images

It may not be easy for most people to admit, but certain national holidays often get a little muddled in their minds—namely, Memorial Day and Veterans Day美女视频黄频大全视频. Clearly, the U.S. Department of Veterans Affairs has seen and/or been asked about the confusion enough times that they dedicated space on to explaining the difference between these two similarly themed, but very different, holidays.

When is Memorial Day and when is Veterans Day?

Memorial Day and Veterans Day are held approximately six months apart: Veterans Day is celebrated every November 11, and Memorial Day takes place on the last Monday of May as part of a three-day weekend that's typically packed with parades and plenty of retail sales promotions. You probably realize both are intended to acknowledge the contributions of those brave individuals who have served in the United States military, but you may not recall the important distinction between the two. So what's the difference?

Veterans Day used to be Armistice Day

Veterans Day was originally known as Armistice Day. It was first on November 11, 1919, the one-year anniversary of the end of World War I. Congress passed a resolution making it an annual observance in 1926. It became a national holiday in 1938. In 1954, President Dwight D. Eisenhower changed the name from Armistice Day to Veterans Day美女视频黄频大全视频 to veterans of the two world wars. The intention is to celebrate all military veterans, living or dead, who have served the country, with an emphasis on thanking the people in our lives who have spent time in uniform for their service to this country.

Who does Memorial Day honor?

Memorial Day is also a celebration of military veterans, but the mood is more somber. The occasion is for those who died while serving their country. The day was first observed in the wake of the Civil War, where local communities organized tributes around the grave sites of fallen soldiers. The observation was originally called Decoration Day because the graves were adorned with flowers.

It was originally held on May 30 because that date wasn't the anniversary for any battle in particular and all soldiers could be honored. (The date was recognized by northern states, with southern states choosing different days.) After World War I, the day shifted from remembering the fallen in the Civil War to those who had perished in all of America's conflicts. It gradually became known as Memorial Day and was declared a federal holiday and moved to the last Monday in May to organize a three-day weekend beginning in 1971.

The easiest way to think of the two holidays is to consider Veterans Day a time to shake the hand of a veteran who stood up for our freedoms. Memorial Day is a time to remember and honor those who are no longer around to receive your gratitude personally.

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