Food Safety Minister Andrew Hoggard said he was following the situation closely and had confidence in New Zealand Food Safety (NZFS), which is investigating.
A spokeswoman for Woolworths confirmed this afternoon that a rat had been seen on a camera in the store.
Yesterday another rat was caught at the store - the 24th - after Woolworths said it was "addressing the situation appropriately" on Monday last week.
The Countdown at 323 Andersons Bay Rd, in South Dunedin, has been closed since Friday as it deals with the problem.
The supermarket needs a day without a rat capture and then a 48-hour "clear air" period before it can reopen.
A NZ Food Safety spokesman said today seeing a rat on camera meant this period had not yet begun.
So the earliest the store can now reopen is Monday.
Mr Hoggard said he was getting daily updates from NZFS officials.
"People are right to expect the highest hygiene standards at supermarkets," he said.
"I’m confident NZFS is focused on keeping consumers safe and holding Woolworths to account, I will continue to closely monitor the situation, and follow the progress of the investigation."
A staff member approached the Otago Daily Times last month with accounts of a rat-infested store.
Concerns were raised store management was not taking the issue seriously at the time.
Then a photo, taken in November last year, was supplied to the ODT, which Woolworths confirmed showed a rat in its Countdown Dunedin South deli section.
Then after rat captures were reported and the store was closed for increased pest control efforts several more photos emerged.
In one photo a rat appears to be trapped in an upturned shopping basket.
In another rat droppings surround a mixing bowl in what appears to be the supermarket's bakery.
Rodent sightings have also increased elsewhere in the country.
A video of a mouse in a deli at Christchurch’s Countdown Eastgate emerged, prompting a wider review of Woolworths pest management practices.
NZFS deputy director general Vincent Arbuckle said the purpose of the Dunedin investigation was to establish the causes of the problem and make whatever changes necessary to prevent it from happening in future.
In some cases, investigations included determining whether enforcement or prosecution action was necessary.
"This includes working with the company to gather information.
"Given the level of public interest in this matter, we will reassure the public that we think it is appropriate to reopen the store."