Gary Morrison, 56, the proprietor of Wings & Finns seafood restaurant at the Tooradin airfield, pleaded guilty in Dandenong Magistrates Court last Friday to several breaches of the Food Act.

After viewing photographs taken at the temporarily closed premises, magistrate Fiona Stewart condemned the "disgraceful state of affairs".

Fining Morrison $26,000 with $4000 costs, Ms Stewart said the penalty needed to act as a general deterrent and send a clear message about the need to protect the health of the general public.

"Clearly that was placed in jeopardy ... anyone eating in these premises must have been in some risk of sickness at the very least."

Maria Macri, appearing for Casey Council, told the court the charges arose from several visits by a food safety inspector in February and March.

The inspector reported finding multiple breaches including rodent droppings in a walk-in dry store area, or pantry, attached to the kitchen, uncovered food in the refrigerator and an inadequate cleaning schedule.

In a follow-up visit, only 10 of 18 requirements had been implemented and rodent droppings were still present in the pantry. A piece of raw chicken was found under a freezer and uncovered, and improperly labelled food was sighted.

Other breaches detected included food being stored on the floor and a mouse scuttling past the inspector.

Appearing for Morrison, Nicholas Tweedie said his client had "inherited" the restaurant when he took over a lease for the entire airfield.

Morrison had "little if anything" to do with running the restaurant and relied on staff to keep the premises in order and a system that had worked well for about six years and lulled him into a false sense of security.

When Mr Tweedie submitted that extensive renovation works had made it hard to control pests, Ms Stewart replied: "The restaurant should have been closed. It's just as simple as that".

The court heard Morrison was formalising the paperwork to sub-lease the restaurant to another party and the premises would reopen under new management.

"He will not be involved in running the business. He accepts it's something he doesn't have the time or expertise to supervise properly," Mr Tweedie said.