A federally funded center to protect the nation's food supply from terrorists opened Tuesday at the University of Minnesota.

Homeland Security Secretary Tom Ridge (search) and Agricultural Secretary Ann Veneman (search) were on hand to mark the startup of the Center for Post-Harvest Food Protection and Defense, a collaboration that includes educators, growers, food companies and retailers.

The center, funded by a $15 million, three-year grant, is one of four university-based centers planned around the nation.

Ridge also announced plans for a center focusing on the behavioral and social aspects of terrorism. Already approved are centers on animal diseases at Texas A&M University and economic analysis of terrorism at the University of Southern California.

"Partnership between the government and our great research universities, businesses and scientists produce together what would be impossible individually," Ridge said.

In Minnesota, the work will range widely, from detecting tiny amounts of dangerous substances in food to checking who has access to food before it reaches consumers.

Overseeing the supply chain is a huge job. Food is imported from around the world by ship, train, truck and air, and goes through processing and packaging plants before heading to markets, restaurants and homes.

Supervalu Inc., the nation's largest food distributor, is among companies working on the food safety center. Since the 2001 terrorist attacks, Supervalu has paid more attention to the possibility of intentional contamination, especially in fruits, vegetables, meats and fish, said David Wiemer, director of quality assurance for the Eden Prairie-based company.

Wholesalers, retailers, manufacturers, farmers and growers — "the entire supply chain" — must work with regulators to share information when anything appears to be abnormal, he said.