OTTAWA -- Nearly a year after tainted Alberta beef sickened 18 people, briefly blocked exports to the U.S. and cast doubts on the safety of Canada's food supply, no one can say for sure what led to the largest meat recall in Canadian history.

It could have been a horde of germs from a contaminated animal passing through a super shredder, a new report suggests. Or an improperly decontaminated carcass. Or simply a case of too much bacteria for the plant to handle.

One thing is for certain: neither staff nor federal inspectors at the XL Foods plant in Brooks, Alta., were taking food safety seriously enough last September to prevent the crisis from happening, a three-member review panel has concluded.

"We found a relaxed attitude towards applying mandatory procedures -- clearly outlined in some documents, less so in others ... a shortcoming shared by both plant and CFIA staff," says the report released Wednesday.

"We found one of the country's largest beef processors unprepared to handle what turned out to be the largest beef recall in Canadian history. As the company had never conducted any mock recalls on a scale that remotely mimicked a real event, XL Foods Inc. found itself overwhelmed with the recall that occurred.

"In short, we found a weak food safety culture at the Brooks plant, shared by both plant management and CFIA staff."

Seemingly obvious tasks -- properly cleaning the germ-infested equipment with which the meat came into contact, for instance -- might have limited the outbreak of E. coli, the report says.

"It is the panel's view that equipment maintenance and sanitation were significant problems at the plant."

The governing Conservatives welcomed the report with plans to spend $16 million over three years to set up inspection teams, complete with 30 new inspectors, to do spot checks on all food plants across the country.

"These highly skilled teams will conducted unannounced spot checks at any federally inspected plants across Canada," said Agriculture Minister Gerry Ritz.

"They will assess the plant's food safety controls and operations as well as the corresponding inspection activities."

The government and the inspection agency are working to implement the other panel recommendations, Ritz added. "Food safety," he said, "is not static."

Panel members Ron Lewis, Andre Corriveau and Ron Usborne were charged with determining how the contamination occurred and how authorities responded to the crisis.

In a statement, they said Canada's food-safety system needs "continuous improvement, vigilance and commitment" to maintain its standing as one of the world's best.

"It is our hope that we have captured the essential elements of the event and subsequent recall and that positive results will accrue from our recommendations," they said.

The contamination at the XL Foods plant last September left thousands of tonnes of suspect beef to be disposed of in what the report described as the largest such recall ever in Canada.

At the time of the E. coli outbreak, the plant was the largest Canadian-owned beef slaughter facility in the country.

It is now owned and operated by JBS Food Canada, a subsidiary of JBS South America.