A teenager died in his girlfriend's arms after eating a grilled chicken burger marinaded in buttermilk from Byron.

Eighteen-year-old Owen Carey, a former pupil at Skinners School in Tunbridge Wells was allergic to dairy and suffered a fatal reaction after eating the burger.

The sixth former, of Crowborough, East Sussex, died hours after dining at the upmarket burger chain's O2 outlet in Greenwich in April 2017.

Food outlets have faced mounting scrutiny of their food allergy policies following an inquest last year into the death of Natasha Ednan-Laperouse, 15, who died of an allergic reaction after eating sesame seeds contained in a Pret a Manger baguette.

Natasha's parents, Nadim and Tanya, are supporting Owen's family.

Today, assistant Southwark Coroner Briony Ballard said introducing a distinct mark next to all items containing an allergic ingredient may prevent further tragedies as she questioned Byron bosses.

The inquest heard four members of Byron's waiting staff who could have taken Owen’s order could not be reached or refused to give evidence to the inquest.

Aimee Leitner-Hopps, Byron's head of food and compliance, denied any wrongdoing by the firm.

She defended its menus and staff training, saying all local authority inspections had been passed and a spot-check by independent consultants Food Alert the day before Owen's death.

Ms Leitner-Hopps blamed an “assumption” being made when the order was made that the skinny chicken burger did not contain dairy products, and said the “green” marinade was “quite clear” on the chicken breast.

She denied the “fine print” placement of allergy warnings on Byron’s menus were “shifting the responsibility” to customers, and said the reason later versions included the words ‘marinaded in buttermilk’ were because buttermilk was becoming “fashionable”.

But Ms Ballard said she “doesn’t see the problem” with having a “simple red A” next to nearly every menu item which contains an allergen after criticising Byron for having allergy warnings in “fine print” on their menus at the time.

Ms Ballard, who said the “error appears to be at the point of the ordering”, pointed out the allergy warning was on the back of the double-side menu in black font against a blue background.

Earlier the inquest heard Byron had changed its menus to state its chicken burgers were marinaded in buttermilk and staff were now required to ask customers if they had any allergies.

The coroner asked: “There was a suggestion in attempting to persuade me that Owen hadn’t mentioned his allergy of dairy or not. That an individual of his age may be embarrassed by the stigma.

“How do you as a organisation approach that?”

Ms Leitner-Hopps said: “In October of last year following quite a few conferences where charities had attended and had highlighted for example one in 10 six to 14-year-olds hid they have an allergy.

"After some higprofileie media cases, we decided that we would take the first step and introduce the step of asking customers if they have an allergy.”

She denied the menu change to include that skinny chicken burgers were ‘marinaded in buttermilk’ in November 2017 was due to Owen’s death.

She said: “We chose to highlight something which had become quite fashionable at the time.”

Clodagh Bradley QC, representing the family, asked: "As you will see it refers to marinaded in buttermilk on it.

"Is the reason that you changed that description because the menu in April 2017 was far from clear and didn’t enable customers or waiting staff who were advancing this menu that it contained buttermilk?"

"We felt the whole matter revolves around the conversation that happens and did not happen at the table at the time of ordering..." - Lucy Urquhart

Ms Leitner-Hopps said she did not know of the food being linked to Owen's death until late February 2018.

She said: “All I had was a simple request by the coroner for ingredients.

“The (marinaded) item came on in 2014 and between 2014 and late 2017 I’m not aware anybody being misled.

"We’ve had no customers that had informed us that thy had felt the chicken was plain and had ordered it in that aspect.”

She confirmed she would not know if a customer had alerted the staff after being misled by the menu.

Lucy Urquhart, from the Royal Borough of Greenwich’s Trading Standards department, said: “We felt that the whole matter revolves around the conversation that happens and did not happen at the table at the time of ordering.

"For whatever reason Byron’s allergy policies and procedures were not triggered."

The inquest heard even if Owen had been carrying his epipen he could not have been saved.

Dr Robert John Boyle, a consultant paediatric analyst at St Mary's Hospital, told the hearing: "There are very few things so powerful that they can take away a young life that quickly.

"We cannot be completely certain whether or not an epipen would have made a difference.

"I think, personally, that it would have been unlikely that an epipen would have made a difference. It sounds like he was extremely difficult to resuscitate."

Paramedics found him unresponsive and surrounded by bystanders, including off-duty medics, an hour after he had eaten the burger.

Doctors continued to perform CPR and paramedics extracted 1.5 litres of vomit from Owen's airways with a suction device, the inquest heard.

Five shots of adrenaline were administered and one of hydrocortisol for anaphylactic shock.

Owen was rushed into A&E, but was pronounced dead shortly after arrival.

The inquest heard Owen had been going to hospital twice a year due to his asthma and suffered various other allergies.

Giving evidence top paediatrician Dr Robert Boyle told Southwark Coroner's Court: "I do think there's a real failure to learn from the tragic occurrence.

"We probably had 150 deaths like this in the UK over the last 15 years. I just don't think we are learning enough as it is."

Calling for a national register for food allergy deaths, he added: "It would be just to understand what are the risks that lead to fatal food anaphylaxis.

"I think the Food Standards Agency have a sort of regulatory governmental role and are quite interested in food allergies.

"I think they would need to be involved and the Anaphylactic Campaign; they would love to be involved."

The inquest continues.

Read more: All the latest news from Tunbridge Wells