WALLINGFORD, Conn. – Students at Sheehan High School have received a little extra protein in their fruit cups, and their parents aren’t happy about it.

Several students posted pictures online of fruit worms that they’ve discovered in their school lunch fruit cups in recent weeks, prompting school officials to launch an investigation into the problem, the Record-Journal reports.

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School food services director Sharlene Wong confirmed that a single fruit worm was found in one fruit cup, and it was sent to a lab for testing, but called the issue an “isolated incident.”

“It was a fruit worm that was found in the cupped fruit,” Wong wrote, according to the news site. “The distributor was contacted and a (quality assurance) review started. The company came to pick up the worm and the supposed fruit cup it was in. My understanding is that it is being sent to a lab for testing.”

But parents aren’t buying the “isolated incident” line, and have taken to Facebook to voice their frustrations and post pictures taken by students of worms and moldy bread served at Sheehan High School.

Kimberly Davidson told the news site her daughter sent her a picture of a worm she found in her fruit cup several weeks ago. The daughter of a friend, Gini Selvaggi, reported the same type of worm in her fruit Friday.

“What are they feeding our kids?” Davidson questioned. “It looks like a maggot.”

“It’s kind of gross that this is an ongoing problem,” Selvaggi added.

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Wong said the district received a letter from the fruit canning company that essentially said these things happen sometimes.

“They stated that ‘organic matter’ can appear because it is impossible for fruit to be effect free due to the limited amount of pesticides being used in orchards,” Wong wrote, according to the Record-Journal.

“The process thousands of pounds of fruit through the high speed processing line and a fruit worm could be in the middle of a piece of fruit and make it into the can. The canning process cooks the organic material,” she wrote. “They stated there was no danger of any foreign matter surviving.”

Gale Ridge, an entomologist with the Connecticut Agricultural Experiment Station, told WFSB the worms found in the fruit appear to be dead.

“The larva shows morphology consistent with having been cooked,” Ridge said.

Wong insisted it’s the first time in her 30 years in school nutrition that a student has found a worm in their fruit, and denied sanitation in the school cafeteria played into the problem.

“I don’t think we have a problem at this school,” she said. “I think it was probably an isolated incident.”

Davidson strongly disagrees.

“Wednesday, I’m in the Guidance Office and I hear some kids talking, showing pictures how they discovered a worm in their fruit cup. This was this week and there were like three other kids,” Davidson told WFSB.

Superintendent Salvatore Menzo told the Record-Journal that parents who have concerns about school meals should contact Wong directly.

Davidson said she left a message with school staff about the worms and never received a reply.