Sometimes, there’s nothing better than a good cry. This is especially true when chopping onions, although not for the emotional release. The component in that pungent misty stuff in onions that irritates the heck out of our eyes is scientifically known as lachrymatory factor, appropriately derived from the Latin word lacrima, which means “tear”. Interestingly enough, lachrymatory factor is actually doing us a a few excellent health favors, possibly even protecting us against cancer. Doesn’t seem like such a terrible chore now, does it?
Onions are naturally rich in two health-benefiting compounds: flavonoids and sulfur-containing compounds. Flavonoids are typically found at high concentrations in the skin and outer layers of onions with yellow, brown, red, or purple coloring. These compounds are also potential antioxidants that could protect us against heart disease, cancer, and aging. The sulfur-containing compounds are where onions give us their taste, odor, and – you guessed it – misty tear gas. So what does this mean?
When an onion is cut, sulfur compounds are released into the air. These compounds are broken down into an unstable intermediate and can then either turn into lachrymatory factor or spontaneously turn into thiosulfinate. This thiosulfinate is not only responsible for the onion’s distinct odor and flavor, but also converts into other sulfur-containing compounds with potential health benefits including anti-inflammation, anti-blood clotting, anti-cancer, anti-asthma, and lowering cholesterol levels. Sounds great to me, and I don’t even like onions!
Maybe you do enjoy onions in your favorite Thanksgiving recipes but you don’t particularly enjoy crying – who could blame you? Never fear; scientists have been working on bringing tear-free onions to the general market since 2008. Tear-free onions were originally developed by Crop & Food Research of New Zealand and House Foods Corporation of Japan. These onions look and taste like regular onions but have lowered activity of lachrymatory-factor synthase through genetic modification and thus do not make your eyes water upon chopping or crushing, but still increase the production of beneficial thiosulfinate – which means none of the tears with all of the health benefits!
Unfortunately, commercializing genetically modified foods is no simple task, so it will probably be a few more years before we find tear-free onions in the Wegman’s produce section. However, the largest share of the liquids and therefore, of the phosphates that make us cry are found in the tips of the bulb – the northern and southern hemispheres, you might say. To avoid getting too much juice out into the air and minimize the crying, try not to cut into the poles too much. This is why classical French technique only has you cut into the poles once, as demonstrated here for a tear-free Thanksgiving feast preparation:
In the meantime, keep chopping your onions with the knowledge that through your tears come wonderful health benefits! And hey, while you’re at it, check out our Turkey Day Turkeys playlist and tell us which “turkeys” you think we should add!