‘The lessons . . . are that laws regulating food production are not mere technicalities.’

The Jalisco cheese poisoning epidemic of 1985--the biggest food contamination case in California history--is a whodunit that still baffles health and law enforcement officials.

Almost from the time Los Angeles County health officials picked up signals that a major food poisoning outbreak was rolling through the area--in April, 1985--until the case was shut last year, everyone was sure of the culprit.

But no one knows for sure how the contamination occurred.

The outbreak killed 40 people, 38 infants or stillborn babies and two adults, said Dr. Ben Werner of the state Department of Health Service. Los Angeles-area Latinos were particularly hard hit among the 103 food poisoning cases connected to cheeses made by Jalisco Mexican Products Inc. of Artesia.

“This was one of the largest of the Listeria outbreaks in the world,” Werner said.

Jalisco’s plant was padlocked on June 13, 1985, and tons of its cheese were recalled and destroyed after health authorities connected the epidemic to the firm’s cheese products.

Investigators and scientists who had descended on the plant were sure of what triggered the epidemic:

The culprit, they said, was Listeria monocytogenes-- a dangerous bacterium that the Food and Drug Administration says is supposed to be killed by proper pasteurization. The bacteria was found in some of Jalisco’s Mexican-style soft cheese products.

But despite months of investigation, no one could pinpoint how the outbreak started--whether the contamination came from raw materials supplied to Jalisco, from unsanitary conditions in the plant or whether the plant’s pasteurization process broke down.

In 1986, Jalisco’s owner, Gary S. McPherson, a former accountant, and his chief cheese maker, Jose Luis Medina, pleaded no contest to misdemeanor criminal charges. They were sentenced to 30 days and 60 days, respectively, in Los Angeles County jail and fined a total of about $48,000.

McPherson, 47, of Pasadena, now a partner in a non-food business, said his friends and business associates did not abandon him, but the Jalisco experience was a bitter one. “Nobody said life was going to be easy,” he said.

Life after Jalisco was tougher for cheese maker Medina, 46. His lawyer, Ken Sabo, said that after getting out of jail Medina picked tomatoes to make ends meet. Now, Sabo said, Medina is driving a truck.

“The lessons for the business community and law enforcement are that California laws regulating food production are not mere technicalities,” said Thomas A. Papageorge, chief of the Los Angeles County district attorney’s consumer protection division, who spearheaded the investigation.

From the Jalisco outbreak came tougher state and federal food inspection laws and a number of federal dairy food recalls. In California, new laws tightened dairy licensing and record-keeping requirements; an undercover cheese plant investigator was hired by the state Department of Food and Agriculture.

About 150 civil lawsuits were generated by the outbreak, said attorney Roy Brisbois, partner in a Los Angeles law firm representing Jalisco interests. A Superior Court trial is scheduled to start next April in which Jalisco is accusing Alta-Dena Certified Dairy--Jalisco’s milk supplier--of being the contamination source.

Alta-Dena’s lawyer, Raymond A. Novell, said the City of Industry-based dairy “wasn’t involved in the outbreak. We intend to show that at the time of the trial.”