The yellow onion variety is being marketed as "the first tearless onion available to the market" and is a result of more than three decades of conventional breeding efforts. While onions usually become more pungent while being stored, this variety becomes milder and sweeter over time.

The onions are the invention of Rick Watson, a plant breeder working for the German chemical company BASF. He began working on the innovation in the late 1980s, using natural techniques rather than genetic modification to create the unique variety.

The onions are the invention of Rick Watson, a plant breeder working for the German chemical company BASF. He began working on the innovation in the late 1980s, using natural techniques rather than genetic modification to create the unique variety.

Pilot sales of Sunions started in Italy in December 2021 and in the UK and France in January 2022. In Germany, it will hit supermarket shelves from February. It was already launched in the U.S. and Canada in 2017 and in Spain in 2020. The fresh onions will be marketed by trading partners under the brand name Sunions.

“The tearless onion is a clear example of our ambition to make healthy eating enjoyable,” says Bilgehan Suer, Regional Crop Lead at Vegetable Seeds and project leader for Sunions Europe. “Different consumer studies confirmed that consumers love to eat Sunions raw as much as baked, stir-fried and cooked.”

Grown from a seed variety from the Nunhems portfolio, Sunions have been introduced to the market in collaboration with value chain partners, with BASF providing the seeds, growing recommendations, quality assurance and connecting the chain partners from ‘farm to fork’. The use of the brand name is part of the cooperation agreement.

It is said volatile compounds in onions are responsible for the tears and pungent flavour, and the amounts of those compounds in other onions remain the same or increase over time. In Sunions, these compounds do the opposite and decrease to create a tearless, sweet and mild onion.

Sunions, which cost more than standard onions, are already on sale in America but have not been universally well-received.

A 2018 review in the Washington Post said they were very sweet - “sweet enough that you could sit there and eat them like popcorn” - and barely had any scent.

Another journalist who tried them said they were “almost flavourless”.

In this pilot phase, Sunions are only delivered to a reduced number of stores inside a limited number of supermarket chains in France, Germany, Italy and United Kingdom.

“If the pilot projects reveal success with consumers, distribution will be extended next season,” says Suer. “What countries will be considered next depends on local interest from consumers and the available supply options.”