Roasted pork that was purchased from a Minneapolis market and resold at a street festival was the "likely initial source" of a salmonella outbreak that sickened 80 people in August, a Minnesota Department of Agriculture investigation concluded.

The food poisoning incident has already put the street festival organizer, New York Plaza Produce, out of business and prompted the city to fine the company $1,000 for violations that included the illegal slaughter of guinea pigs for food. Now, state records obtained by the Star Tribune describe how the salmonella was traced to three whole roasted pigs that New York Plaza Produce owner Nieves Riera bought from Shuang Hur BBQ on Nicollet Avenue.

An Agriculture Department investigator determined the pork probably had low levels of salmonella when Riera bought it, but the salmonella likely grew and spread through cross-contamination. The state sent New York Plaza Produce a "notice of warning" earlier this month, a typical penalty for a first violation.

Attorneys for Riera say the market should be held responsible for selling the tainted pig. Khan Huang, owner of Shuang Hur BBQ, said the pork was not intended for resale.

The Department of Agriculture, which licenses New York Plaza Produce, began its investigation after reports of gastrointestinal problems among those who served food at the Aug. 11 Ecuadorian Independence Day celebration on E. Lake Street.

Carrie Rigdon, one of the investigators in the case, said meat purchased at a retail market should not be resold.

"The fact that there was further preparation and serving at the festival, and that it was a multi-hour process, it's likely that any contamination just multiplied" and cross-contaminated rice, beans and guinea pig meat, Rigdon said.

"If not held at the right temperature, you get into this zone where any salmonella is really happy and keeps growing," she said.

Attorneys Boris Parker and Jordan Anderson, who represent Riera and the business, said Riera felt "very distraught" after learning that dozens fell ill at the festival, which she has hosted for several years. Parker said they have statements from various attendees who say they did not get sick from eating her food, and those who did likely ate food that was contaminated before Riera served it.

"Her suspicion was that the issue was with the pork," Parker said. "We are not saying that she could not have been more careful to avoid the problem, but the root cause was not her or her food." Parker said given the bulk of Riera's purchase, Huang should have known the pork was going to be resold.

On Aug. 15, Minneapolis officials visited New York Plaza Produce "and said it does not look like a primary wholesaler (just retail) and it does not look in good condition," said a Department of Agriculture report. The inspectors also found "additional product that had been cooked at this facility in preparation for another upcoming event" in northeast Minneapolis.

"During the inspection, a member of the public had come by to state they had gotten sick from the pork served by Ms. Riera at the August 11 event," the report said.

In an Oct. 8 letter, the department told Huang that "even though you state you were unaware that your retail roasted pigs were being sold at the Ecuadorian Festival it is still a violation … and you are required to make every effort possible to inform your retail customers that they cannot resell your retail processed meat."

Huang said in his 20 years in business, his pork has never been an issue. He said he is "not selling to Ecuadorian customers" because he does not want to risk another situation like this one. He said he thought the three pigs were going to be served at a private party.

In addition to the violation of reselling the pork, Riera was not authorized to slaughter guinea pigs, a traditional Ecuadorian food known as "cuy."

The investigation revealed that Riera purchased two frozen guinea pigs from a Minneapolis store and a dozen guinea pigs on Aug. 8 from Gary Ash in Cedar, Minn. Ash told investigators that Riera purchases 10 to 12 guinea pigs every two or three months. Tests of the feces in the enclosures where the guinea pigs were held tested negative for salmonella, the report said.

After obtaining the animals, Riera "cut the necks of the guinea pigs, drained the blood, removed the fur with hot water and then washed the guinea pigs with cold water," the report said.

Riera's attorneys said they are working to get the city's fine reduced, but she will ultimately pay "whatever is finally imposed." Riera has surrendered the licenses for her business and plans to find a tenant for the closed market's building at 1304 E. Lake St.

"Our client is not running away from responsibility," Parker said.

Alejandra Matos • 612-673-4028 •

Twitter: @amatos12