OTTAWA - The beginnings of last summer's deadly listeriosis outbreak lay in a binder at a Maple Leaf Foods plant in Toronto, the head of the company said Monday.

That's where Maple Leaf logged the results of its Listeria testing. Had anyone analyzed the data in that binder, they might have noticed more frequent bouts of the bacteria last May.

But no one did. Maple Leaf president Michael McCain said the company didn't have to at the time.

And so it was that the Canadian Food Inspection Agency wasn't alerted to suspect Maple Leaf deli meats until early August -- more than two months after the company first noticed an uptick in positive Listeria tests at its Bartor Road plant.

Public health authorities in Ontario advised the CFIA on Aug. 6, 2008 they suspected tainted food was linked to cases of listeriosis in the province.

There was nothing stopping a CFIA meat inspector at the plant from leafing through the binder, McCain told a parliamentary subcommittee on food safety.

"The relative obligation of who has the obligation to point out particular test results is certainly an issue," he said. "But the test data was made available. ...

"(CFIA inspectors) have an obligation and were at our facility each and every day."

McCain said the company wasn't obliged at the time to keep records on its Listeria testing, but did so anyway.

But because Maple Leaf didn't scrutinize the data for trends and patterns, as it now does, he said the company couldn't have known it had the beginnings of an outbreak at hand.

"We were collecting a mountain of data at that time," McCain said.

"It's voluminous data. It's very scientific data. it's highly interpretative data. You have to spend the time and energy to examine it all.

"In retrospect, you know, we've said we should have known that. We should have had the systems in place to see that. Others could have come to the same conclusion."

McCain acknowledged the listeriosis outbreak, which killed 21 people and sickened hundreds more, might have been prevented had Maple Leaf studied patterns in its testing.

Prior to the outbreak, each time Maple Leaf found Listeria in its plants, it cleaned the site and re-tested several times for bacteria. The company considered the Listeria gone if it didn't turn up in successive tests.

Listeria can cause listeriosis, a foodborne illness that causes high fever, headache, neck stiffness and nausea that is of particular concern to the elderly, pregnant women and the infirm.

Maple Leaf apologized last summer after the outbreak was traced to equipment in a Toronto processing plant, which was temporarily closed during the crisis. The company has agreed to pay up to $27 million to settle class-action lawsuits.

Maple Leaf has since instituted more rigorous testing for Listeria in plants producing ready-to-eat meat.

Under new regulations enacted this month, companies must now report all positive Listeria findings to the CFIA.

Senior CFIA officials also appeared before the food safety subcommittee on Monday.

Their appearance comes after four reports into last summer's deadly listeriosis crisis were released last Friday.

Reports by the CFIA, Health Canada, the Public Health Agency of Canada and the Ontario government describe a food safety regime short on meat-hygiene expertise that needs clarity on who identifies root-cause problems and has trouble tracking problematic food products.