The jury in the Heather Stacey murder trial has heard that the accused was out buying her chips when she died.
Alan Cameron, 56, said he left the 44-year-old for just 20 minutes to pick up the food and when he returned she was dead.
He claimed that he did not tell police about the death because he "panicked" over an outstanding arrest warrant for him.
Mr Cameron denies murdering Ms Stacey at her flat in Edinburgh in 2007.
He has admitted hiding her body in her flat in the Granton area of the city for more than a year and dismembering and dumping her remains.
'She had died'
The remains of the mother-of-four, who was from Dingwall, were found in a bag by a dog walker in Edinburgh on Hogmanay 2008.
Cameron made the claims during an interview which was read out to the jury at the trial at the High Court in Livingston.
The court heard that during the interview on 8 January 2008, at St Leonard's Police Station in Edinburgh, Mr Cameron told officers: "It was the first two weeks of December 2007.
"She said she was hungry and I went to the chip shop to get her something to eat.
"When I came back she was sitting in bed. I went and said 'there's your food' and, well, she had died.
"I don't know what had happened or if she had had a heart attack or if it was due to the drink.
"I shook her to see, thinking she was sleeping but there was no life.
"I panicked and, I know any normal human being would have phoned the authorities right away but I panicked."
Stayed in flat
Edinburgh Sheriff Court issued a warrant for Cameron on 5 September 2007 after he failed to turn up to answer claims he kicked a dog in July that year.
The court heard that Mr Cameron had said he was worried that if he reported Ms Stacey's death he would be picked up as well and that nobody would believe how Ms Stacey died.
The court has also been told that Mr Cameron stayed in the flat with the body for months until in November 2008 he received a letter from the City of Edinburgh Council telling Ms Stacey that she was being evicted over unpaid rent.
The trial before Judge Lord Matthews continues.