The dinner-table habit Grace Dent says is a relationship dealbreaker

After years of judging food from behind and in front of the restaurant pass, Celebrity Masterchef judges Grace Dent and Giorgio Locatelli have seen every food faux pas imaginable, from hot sauce smuggling to shocking table manners.

We asked them to rate six common food faux pas. Some they were surprisingly chilled out about – one was labelled "socially criminal."

Acceptability score: 3/5

"It is ignorant," says Giorgio. "When somebody says that to me, I always say, 'have you ever tasted Stilton?'"

Grace is more forgiving and doesn't actually disagree with the statement – although she does come to British food's defense.

"There's a beauty in the blandness," she says.

"When I've been away all over the world and things are bright and fiery and spicy… I want to come back and eat beige things. I want oven chips."

Acceptability score: 4/5

This is where the judges show some unexpected sympathy – and even affiliation with condiment offenders.

"I carry around hot sauce with me," admits Grace.

"I think that sometimes food is really boring and badly made and you need something to lift it."

Although she stresses subtlety is everything.

"If you're spotted taking your own sauce out of your bag, it looks like you're a difficult character in the restaurant."

Giorgio says simply with a shrug of his shoulders, "You're responsible for your plate. If you want to put crap in there, that's your choice."

Acceptability score: 1/5

They are both in agreement here.

"It's such a rude thing to do," says Giorgio.

"When I was a little girl," says Grace, "my father seasoned every single thing before my mother had even put it on the table… It drove me mad!"

Acceptability score: 0/5

This was the only habit to score a perfect zero – and neither judge held back.

"You need to break up with them," is Grace's advice to anyone who finds themselves dating an open-mouthed eater. That's how strongly she feels about it.

"Table manners are important," says Giorgio a little more diplomatically, while making it clear that sound effects are never okay.

Acceptability score: 1/5

There's a unanimous verdict that this one is "socially criminal."

It's even worse if you're a guest at someone's house, says Giorgio.

"If I'm invited to dinner, I'd rather put the food in my pocket and walk away with it than complain.

"If you ask for something like steak and ask for it well done, and they bring it to you rare, you've got a case to send it back. But even then I would just eat around the edges."

Grace is in agreement. "Even though I'm a restaurant critic, [I feel] exactly [the same]. I would just eat it."

Acceptability score: 5/5

Our judges have no issue with this whatsoever.

"You can't expect if you're throwing a dinner party that everything's going to be equal," says Grace.

"You've said, 'I'm having a dinner party, come to mine,' right? You haven't said, 'I'm having a dinner party and everybody needs to bring equal parts.'"

This, alongside the financial outlay and being stuck in the kitchen, is, Grace says, exactly why "you should never have dinner parties" in the first place.

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