Tearless onions: what are Sunions from Waitrose, when do they go on sale - and why do onions make us cry?

As professional and amateur chefs up and down the UK will know, chopping onions can be a tearful business.

There have been numerous attempts to find ways of stopping the bulb vegetable’s infamous sting from reaching our eyes, but none are a perfect science.

Retailer John Lewis sells a pair of ‘onion goggles’ which have good reviews but will set you back a tidy £23.

Meanwhile, there are a wide variety of onion hacks, including chopping them under water or by a vent, that are questionable at best and slightly dangerous at worst.

So the announcement by major supermarket Waitrose that it will launch ‘tearless onions’ could be a major breakthrough.

When will these new onions go on sale - and why do onions make us cry in the first place?

Here’s what you need to know.

Why do onions make us cry?

While the process of chopping onions can bore you to tears, the reason we cry while peeling or dicing the bulbs has nothing to do with emotions.

In fact, it’s our body’s reflex reaction to an irritant released by the vegetable.

As a bulb, onions grow underground where they are vulnerable to insects and other creatures, like voles.

To stop these animals from taking a hefty bite out of them, onions have developed a defence mechanism that sees them release enzymes and a type of acid in the form of an irritant gas -  propanethial S-oxide - if their skin is broken.

When this gas hits water, it turns into sulfuric acid.

Given our eyes have a watery layer which protects our eyeballs, it means the onion’s defence mechanism can cause a nasty sting.

It forces our eyes to activate their own defence - tears - which are designed to flush away harmful substances.

Some people are more prone to crying than others when confronted with an onion.

Waitrose Sunions explained

Not all onions are as good at inflicting human pain and suffering as others.

For example, spring onions only make your nose run a little when you eat them.

But cutting into red and brown onions almost always guarantees tears - until now at least.

Waitrose claims Sunions, which it will stock from next week, are a completely ‘tearless’ variety of the bulb.

The brown onions are said by the supermarket to be ideal for “those with sensitive eyes” or people who are “cooking with children”.

Up until now, the breed of onion has only been available in the USA since its launch in 2020, but Waitrose said it will stock them in some of its stores and online from next Tuesday (18 January).

According to Sunions’ website, the breed of onion has not been genetically modified but has instead been created over three decades through a “natural cross-breeding program”.

And while other types of onion get stronger defence mechanisms as they age, causing more tears, Sunions are said by their developers to become less pungent as the get older.

They also boast a mild flavour, can be eaten raw, and are said to work well in salads or hot meals.

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