A southern Ontario dairy farmer said Wednesday he'll appeal a decision finding him guilty on 15 of 19 charges related to the sale and distribution of raw milk.

Michael Schmidt had been acquitted of all charges by Justice of the Peace Paul Kowarsky in January 2010, but the Ontario government and the Grey Bruce Health Unit appealed that decision.

Lawyers for the provincial government had argued that Kowarsky made critical legal errors when he threw out 19 charges against Durham-based farmer.

Justice Peter Tetley agreed and overturned 15 of the acquittals in a 77-page ruling released Wednesday afternoon in Newmarket.

"It is an appalling ruling," Schmidt said in an interview following the decision. "I cannot understand how one judge can differ literally 100 per cent to another judge."

The Health Protection and Promotion Act makes it illegal to sell unpasteurized milk in Canada because it's considered a health hazard. It is, however, legal to drink raw milk.

During Schmidt's trial last year, food scientists and health experts testified that mandatory pasteurization laws are needed to protect public health.

Schmidt argued that his "cow share" operation -- in which the consumers of the raw milk from his farm were also owners of the milk they drank -- exempted him from the legislation.

Tetley ruled that the Health Protection and Promotion Act and Milk Act were "not given the broad interpretation it required as public welfare legislation" by the trial judge.

Tetley also dismissed all claims that the legislation violated the Canadian Charter of Rights and Freedoms.

"This is just a temporary setback," Schmidt said.

"We will continue to fight, both through the courts and through the legislature, for the rights of individuals to decide what they put into their bodies," he said.

Schmidt's lawyer, Karen Selick, said the decision is still being reviewed but "we have already notified the Ontario government that we will likely be seeking leave to appeal."

Schmidt said he will continue to operate his dairy business.

"I will not change my path," he said.

Selick said she has asked the government not to raid the farm as the case is wends its way through higher courts.

Schmidt's farm was raided in November 2006 by officers from the Ministry of Natural Resources and the Ontario Provincial Police.