Leftovers from Erin Patterson’s beef wellington meal examined by expert showed no trace of death caps

A scientist who examined the leftovers of a beef wellington meal cooked by accused triple murderer Erin Patterson after extracting pieces with tweezers did not find traces of death cap mushrooms, a jury has heard.

A scientist who examined some of the leftovers of the beef wellington cooked by Erin Patterson did not find any traces of death cap mushrooms, a jury has heard.

Mushroom experts, a professor and a waste management worker took to the witness box on the 11th day of Ms Patterson’s triple murder trial, with CCTV footage also shown of the moment a dehydrator was dumped at a local tip.

Ms Patterson, 50, is standing trial in Morwell, accused of murdering her estranged husband’s parents Don and Gail Patterson, both 70, along with Gail’s sister Heather Wilkinson, 66.

They died after she served them individual beef wellingtons allegedly laced with lethal death caps at her Leongatha home on July 29, 2023.

But the prosecution alleges that Ms Patterson’s serve did not contain poisonous mushrooms.

Heather’s husband, pastor Ian Wilkinson, 71, was the only guest to survive.

She has pleaded not guilty to three counts of murder and one count of attempted murder, claiming what happened was a “tragedy and a terrible accident”.

Dr Camille Truong was working as the on-call mycologist, a fungi specialist, for the Victorian Poisons Information Centre on July 31, two days after the lunch.

Dr Camille Truong a research scientist at the Royal Botanical Gardens leaves court in Morwell. Picture: David Crosling

Erin Patterson arriving at her Leongatha home after three people died from a meal she had cooked. Picture: Jason Edwards

She told the Supreme Court on Wednesday she was sent a photo of the leftovers of the beef wellington, which had been fished out of a bin at Ms Patterson’s home by a police officer.

Dr Truong said the photo was sent by Dr Laura Muldoon from Monash Health, who informed her four patients had presented with symptoms of mushroom poisoning.

“I did indicate to (Dr Muldoon) that if the mushrooms were coming from a shop or supermarket, it was extremely unlikely and probably impossible to be death cap mushrooms, because those mushrooms only grow in the wild,” she said.

She added that she also told Dr Muldoon there were “absolutely no sightings of death cap mushrooms” in Victoria over the past couple of months.

“It was highly unlikely to be a case of death cap poisoning.”

The court previously heard the leftovers were sent by “urgent taxi” to Dr Truong’s office at 5pm, but since she was no longer at work, she had them sent to her home.

“I have a small microscope setting in my house,” she described to the court.

“With tweezers, I carefully picked out the little pieces of mushroom … and then I studied them under the microscope.”

Dr Truong said she studied “little pieces of mushroom” from the lunch leftovers under a microscope at her home. Picture: David Crosling

A classic beef wellington as pictured in cook books. Picture: Supplied

The court heard she did not find any death cap mushroom pieces.

She said she popped the bag of leftovers in her fridge and conducted another examination at her office two days later on August 2.

Dr Truong confirmed she only identified field mushrooms, typically found at supermarkets.

Later, the jury was shown CCTV footage from Koonwarra Transfer Station and landfill taken at 11.34am on August 2, four days after the lunch.

In its opening address to the jury, the defence admitted Ms Patterson lied to police about dumping her dehydrator at the tip.

In the footage, a woman exits her car, opens the boot, takes out an item and walks into a shed. She returns to the car empty-handed.

Darren Canty, an operations manager for the Dasma Group, who operates the tip, said one of his employees searched the bin for the item the woman left behind.

The jury was then shown a photo of a black dehydrator laying on its side, which was seized by police on August 4.

Andrew Bersten, an intensive care specialist, also gave evidence on Wednesday, having examined Ms Patterson’s medical records.

Intensive care specialist Professor Andrew Bersten leaves court. Picture: David Crosling

Crown prosecutor Nanette Rogers SC asked: “Is there sufficient evidence in Erin Patterson’s medical files to support the assertion that she was diagnosed with cancer?”

He replied: “I could not find evidence to affirm that statement.”

The court heard Ms Patterson had completed a self-administered cervical screening test in March 2023 and the “results were normal”.

In its opening address, the prosecution alleged that she falsely claimed to have cancer to ensure and to explain why the children were not at the lunch.

The defence has suggested she only told the lunch guests she had a “suspected” diagnosis of cancer.

Professor Bersten also confirmed the medical records showed no evidence of amanita poisoning or toxic mushroom poisoning after she was admitted to hospital following the lunch.

The trial, before Justice Christopher Beale, continues.