An Australian woman who murdered three of her estranged husband's elderly relatives with a poisoned Beef Wellington has been jailed for life.

In the early hours of Monday morning, UK time, Erin Patterson, 50, was handed a minimum 33-year jail sentence.

The case, which has gripped Australia for years, saw Patterson found guilty in July of killing her mother-in-law, Gail Patterson, her father-in-law, Donald Patterson and Gail's sister, Heather Wilkinson.

A jury also found the 50-year-old guilty of the attempted murder of Reverend Ian Wilkinson, Heather's husband, who survived the meal at Patterson's home in Leongatha, Victoria.

Mrs Wilkinson and Mrs Patterson died on August 4, 2023, while Mr Patterson died a day later.

Rev Wilkinson spent seven weeks in hospital - but survived.

He told the court last month how the death of his wife had left him bereft.

"It's a truly horrible thought to live with that somebody could decide to take her life. I only feel half alive without her," he said, breaking down in tears as he delivered a victim impact statement.

Erin Patterson has been found guilty of murdering three of her family members with a poisoned mushroom meal | REUTERS

PICTURED: Erin Patterson arrives at the Supreme Court of Victoria in Melbourne on August 25

Sentencing, Justice Christopher Beale said Patterson's extensive planning lack of remorse meant her sentence should be lengthy.

"The devastating impact of your crimes is not limited to your direct victims. Your crimes have harmed a great many people," he told the Supreme Court of Victoria in Melbourne.

"Not only did you cut short three lives and cause lasting damage to Ian Wilkinson's health, thereby devastating the extended Patterson and Wilkinson families, you inflicted untold suffering on your own children, whom you robbed of their beloved grandparents."

Prosecutors had accused Patterson of knowingly serving the guests lethal death cap mushrooms or "amanita phalloides", but her defence claimed the deaths were a "terrible accident".

After her conviction earlier this year, Australian journalist Adrian Falk told GB News of the extraordinary interest in the case from around the world.

"It has truly gripped Australia and, as you mentioned, the world," Mr Falk told Britain's News Channel.

"The jury took just seven days to reach their verdict, and people have been camping outside in the depths of our winter, sleeping in bags overnight, just to get into the courtroom to witness the trial."