The couple, whose bodies were found on Monday, may have lain undiscovered in their home for up to 18 months
It is understood that as well as checking the use-by dates of food in their fridge and larder, detectives are also forensically examining mobile phones and computers owned by Nicholas and Hilary Smith.
They are also continuing to go through postal and other correspondence in the house to see if there are any clues as to what was going on in the property in the weeks and months before the couple, who are from the UK, died.
Detectives are also speaking to local residents who live in and around the village of Cloneen, in south Tipperary near the remote house where the couple lived for about 10 years.
While the Smiths paid someone €500 to keep cutting the grass for as long as the money lasted, the couple appear not to have widely used the local amenities and services over the last decade.
A number of differing scenarios are being looked as as far as how the couple died. Murder-suicide and double suicide will have to be ruled out.
Toxicology tests may also indicated whether the couple may have succumbed to carbon monoxide poisoning.
Detectives are also understood to be liaising with UK authorities in connection with the couple’s death.
Although post mortems have already been carried out, results are inconclusive and detectives are awaiting the results of the toxicology tests.
The UK authorities might be able to help as far as tracing any relatives of Nicholas, 81, and Hilary, 79.
The snag for the authorities is trying to track down the right ones, given how common the name Nicholas or Nick Smith is.
There were no signs of a forced entry, curtains were drawn – and the couple appear to have indicated to locals they were selling up and moving away in the months and weeks before they vanished from sight.
Since news of the couple’s death broke, the local community has been subjected to “hatred and misinformation”.
A local councillor has said that comments on social media have added to the pain being felt locally.
Local Fine Gael councillor Mark Fitzgerald, whose family own The Thatch pub in Cloneen village, told: “Unfortunately, the full story had not emerged when these bodies were found and there was a lot of hatred and misinformation put out especially on social media and that really compounded the issue.
“There's a lot of hurt and pain in good people in a hard working area.”