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Tearless onions

Chopping onions have always been an irksome chore because of it’s tear inducing

properties when sliced through. This tear inducing property is actually due to syn-

propanethial-S-oxide, which is a sulphur-containing chemical that is released

when onion cells are damaged, causing the various enzymes and other substances
that are normally kept apart to spill out and react together forming an irritating

acid. This acid when comes in contact with the water in your eyes, induces tears.

Knowing this, some research groups have created onions that are genetically

modified to lack an enzyme that leads to syn-propanethial- S-oxide, but
unfortunately these have not yet made it to the market.

While these genetically modified onions have not yet made it to the market,

another tearless onion which is not a product of genetic modification but instead a

product of an all-natural cross-breeding program, has recently made it to the
market and are called sunions. The brand has said that it took more than 30 years

of breeding less pungent varieties of onions to find a variety where the vapours

released on chopping are not powerful enough to bring tears to the eye.

Mr. Levi Pereira
(F.Y.BSc 2021-22)

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