We've been doing it all wrong. (Getty Images)

It’s a topic that causes a lot of divide already, and now Which? has weighed in with a revelation that may surprise ketchup fans.

It doesn’t need to be stored in the fridge.

We can hear people up and down the country shouting “I told you so” as we speak.

As far as condiments go, it turns out we don’t often look at where they need to be stored for optimal consumption, which is why so many of us are left squabbling over where to store them.

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In a bid to educate the nation on how to store their much-loved condiments, the product reviews website surveyed 444 of its members.

Just one in five of us read the labels on things like ketchup and BBQ sauce which is probably why there’s so much debate around where they should live.

“We discovered a lot of confusion, misinformation and downright bad habits - including ones that could be putting their health at risk.” Which? said in a statement.

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Ketchup divides the nation the most, but it doesn’t need to live in the fridge.

Due to the natural acidity of the tomatoes and vinegar, it can be kept in the cupboard. It’s not the only condiment that can be moved from fridge to cupboard, either.

Honey, HP sauce, soy sauce, pickles and malt vinegar can all be exiled from the fridge to the cupboard, too.

Great, that’s plenty of extra room for chocolate (a whole new debate).

If you're putting your ketchup in the fridge then you're doing it wrong. Where do your sauces go?https://t.co/mH4M7QcZ2n pic.twitter.com/zeCY7qe5sf — Which? (@WhichUK) March 3, 2020

Despite the announcement, Heinz has released a statement weighing in with its ketchup expertise.

“Because of its natural acidity, Heinz Ketchup is shelf-stable.

“However, its stability after opening can be affected by storage conditions. We recommend that this product, like any processed food, be refrigerated after opening. Refrigeration will maintain the best product quality after opening.”

Responding to the statement from Heinz, Which? said: “Due to its high vinegar content, plus tomatoes are naturally acidic, there's no requirement to keep ketchup in the fridge. Maybe someone at Heinz just likes cold ketchup on their chips.”

Read more: Simple hacks for reducing food waste

As for other products, which foods really should live in the fridge?

Redcurrant jelly, tartare sauce, maple syrup, salad cream, pesto and mayonnaise, so say Which?

Maple syrup? We’ll be right back.

The research has unsurprisingly left a fair few people scratching their heads and re-arranging their shelves.

Thank goodness for the simplicity of mustard and piccallili which is so uncomplicated it can be stored in fridges and cupboards.

We should all be more like mustard.