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It's a scientific breakthrough that could bring tears to your eyes - but it won't.
New Zealand agricultural scientists, working with their Japanese counterparts, have developed a tearless onion that could banish the pre-dinner blub in the kitchen.
The onion, from Crop & Food Research, looks like a conventional onion but has up to 500 times less of the irritant that induces tears.
To prove it, they've been crushing the onions in the labs - with no tears.
Crop & Food senior scientist Dr Colin Eady said the development was an improvement on "mild" onions, which don't induce tears but lack the flavour of a regular onion.
"That's because they have very low levels of the sulphur compounds which contribute to the health and flavour properties of the onion."
To keep the flavour - but not the tears - the new onion has been developed by silencing the gene that produces the enzyme lachrymatory-factor synthase. The enzyme is released when an onion is cut, setting off a chain of chemical reactions resulting in the forming of an irritant that stimulates the eyes' lachrymal glands, releasing tears.
"What we've done is develop the tearless onion. We anticipate that the health and flavour profiles will actually be enhanced by what we've done.
"What we're hoping is that we'll essentially have a lot of the nice, sweet aromas associated with onions without that associated bitter, pungent, lachrymatory factor."
The breakthrough has caused ripples in international circles. Dr Eady and his Japanese counterparts have presented their results to the 5th International Symposium on Edible Alliaceae, a veritable who's who of agricultural scientists, and his work is the cover story in the December issue of the international onion trade journal Onion World.
The magazine quotes Dr Michael Havey, professor of horticulture at the University of Wisconsin and a leading light in onion science, predicting that tearless onions will become a mainstay in household kitchens around the world. He told Onion World that Dr Eady's work was "clearly the No 1 topic of discussion".
But Dr Eady said the onion was still in the developmental stages - meaning there'll be tears in the kitchen for at least another decade.
Auckland chef Harry Tahana said it was a great development, but commercial kitchens avoid the teary-eyed problem as they either get their onions pre-prepared or store them in the fridge for a few days to reduce their tear-inducing abilities.
