State Agriculture Department investigators Tuesday seized hundreds of gallons raw milk and other food produced by a Gibbon dairy farm that has kept churning out product despite a state order to stop.

Raw milk produced by Mike Hartmann's farm was fingered by the state for eight cases of E. coli O157:H7 in May, and seven instances in July and August of other stomach bugs that cause diarrhea and abdonimal pain.

On Tuesday, state agriculture investigators armed with a search warrant seized "hundreds of gallons of raw milk," along with cream, yogurt, cheese and meat from Roger Hartmann, Mike Hartmann's brother, said Gary Wood, executive director of the Foundation for Consumer Free Choice, an advocacy group to which the Hartmanns also belong.

At the time of the seizure, Roger Hartmann was meeting with customers in Minnetonka, delivering products that had been ordered last week, Wood said. The Agriculture Department declined to comment, saying its investigation into Hartmann is still in progress.

Raw milk isn't pasteurized -- treated with heat to kill pathogens -- and public health authorities widely decry it as dangerous. But some natural food advocates see it as a healthful tonic of sorts, superior in taste and nutrients.

In June, Minnesota's Agriculture Department impounded serveral hundred tubs of dairy foods and other products at Hartmann's farm, and ordered him to stop selling food until alleged unsanitary conditions in his barn were addressed.

But Hartmann has denied that his barn is unclean, and apparently has kept selling raw milk and other products since then. Wood said that there were no contamination issues with the food seized Tuesday.

Minnesota law limits the sale of raw milk to the actual farms at which it's produced.

Hartmann has argued that the state has no regulatory power over his operations because he is a farmer selling directly to consumers and that the Minnesota Constitution gives him that right.

Mike Hughlett • 612-673-7003