Christchurch parents were horrified after their children from Haeata Community Campus ate a contaminated meal from the government's free school lunches programme yesterday.
The school, which had students from Years 1 to 13, said a teacher noticed the lunch was off after they had been distributed to a number of children.
The School Lunch Collective told RNZ it was investigating a "food quality issue" after mouldy mince was served to students.
The Collective represents Compass Group, which was contracted to provide the meals.
Seymour spoke to RNZ's First Up programme about the lunches this morning, accusing Principal Peggy Burrows of being a "media frequent flyer".
"It will be investigated but I also note this particular principal is a frequent flyer in the media complaining about quite a range of government policies... I think people need that context."
"I must admit I was a little bit hurt to be described in that matter from a person who holds a significant portfolio in education and is, at the moment, the Deputy Prime Minister.
"I don't think I've ever met Mr Seymour personally or had a conversation with him."
Earlier this year, Burrows asked to get out of a contract with Compass Group following several weeks of problems and "disappointing" service, but this was denied by the government.
Seymour said what appeared to have happened was that lunches from an earlier day were served to children.
"Whether that happened through the distributor or whether that happened with a mix up at the school is unclear."
He said there had been no illness as a result - that he knew of - and testing was being done to get to the bottom of how it happened.
Labour leader Chris Hipkins today criticised Seymour's response.
"The fact that David Seymour is serving kids mouldy lunches is the problem here - not the fact that the principal is blowing the whistle on it," Hipkins told Morning Report.
Compass Group remains on the list of providers chosen to provide lunches to high schools, intermediate schools and comprehensive schools in 2026.
Students wary of lunches
Burrows said children were wary of the lunches and several students told RNZ they had been put off trying the meals again.
Year 6 student Emily said yesterday's lunches looked "liquidy" and she saw something mysterious and green.
"It makes me feel disgusted and gross," she said.
Another Year 6 student Tamara said she did not feel like eating a school lunch.
"They just put me off after hearing some have a kind of food poisoning or stuff in them. You'd think if they are going give us free meals they would give you good quality meals that aren't going to make you sick."
Year 9 student Alani said she usually ate the lunches if she was hungry, but declared she would never eat them again no matter how starving she was.
Year 7 student Bridie was not been put off the lunches, but said it was clear that many of her classmates were giving them a miss when she took a meal of butter chicken today.
"Other people were staring at me, they were like, 'Oh look at her she's taking a lunch'. My friends were like, 'Bridie don't, don't', but I ate it and then other people started grabbing them."
Burrows said there had been no jump in absences and no reports of children needing treatment for food poisoning.
Girl unwell, mum says
But the mother of a girl who ate a mouldy meal at the school yesterday says she is now unwell.
Rebecca Mckenzie, told RNZ's Morning Report programme that her 12-year-old daughter Aurora was feeling ill.
"She is not looking good at the moment. She has a very queasy tummy and a temperature of 39 [degrees Celsius], looking really quite sick, I'll be ringing my doctor once it's open."
Mckenzie said her daughter had eaten just over half of the meal before throwing it out.
"She said her one didn't look mouldy but it tasted very disgusting. She said it looked very undercooked which is quite normal with what they get served there.
"We rely on these meals and to have this is absolutely appalling, but unfortunately David Seymour wanted to cut the budget back and give us these not so nice meals."
Another parent, Kalah Balir, said her 12-year-old daughter ate half of the meal before realising it was bad.
"She said I was hungry, so I got through half of it, and it was yuck, so I threw it away. I'm angry, I'm disgusted, it's just sick that was served to children. It's dangerous.
"I don't hold any fault with the school, as soon as they were alerted to the problem, they did try to fix it, of course, but the meals are sealed for safety reasons.
"The government just needs to do better, our kids do not deserve this."
MPI testing
The Ministry of Primary Industries (MPI), confirmed it would carry out checks of lunches at the school today.
Food safety said it was working with the Ministry of Education and the National Public Health Service to establish the facts.
It said there was no evidence of any wider food safety issue at this stage.
New Zealand Food Safety deputy director-general Vincent Arbuckle said an investigation had begun.
"We are working with the Ministry of Education and the National Public Health Service to establish the facts. There is no evidence at this stage of any wider food safety issue."
