"Cheese Sizzlers were sent to market packaged as Original Sizzlers, which did not have cheese included in the ingredient list. They were distributed to various outlets, including supermarkets," she said.
"Three children who were allergic to milk complained of allergic reactions after consuming the mispackaged sausages.
"One had a moderate reaction, one a moderate to severe reaction and one a severe anaphylactic reaction that required hospital treatment."
Following these reports from the public, Hellers initiated a recall of the affected product.
Prior to sentencing, Hellers pleaded guilty to one Food Act 2014 charge of failing to ensure food is safe and suitable.
A reserved judgment by District Court Judge J Bergseng was released late yesterday.
The company was fined $39,375 and ordered to pay $5000 to each of the three victims together with court costs of $130.
This is the first time that tougher penalties introduced in the Food Act 2014 have been imposed.
Since the incident, the company has put in place additional staff training and procedures to prevent the problem recurring.
Allergy New Zealand's CEO Mark Dixon said the prosecution was a timely reminder of the need for food businesses to take food allergen management seriously.
"The recent tragic death of Auckland teenager Edyn Rubena-Misilisi shows how dangerous accidental food allergic reactions can be.
"Food allergy is not a life-style choice, it is a challenging condition which needs to be managed all day every day for many thousands of people.
"They need the food industry to comply with regulations on food allergen management and labelling so they are able to access safe and suitable food wherever they are."
Dixon said there has been a significant increase in the past 12 months in food recalls for undeclared allergens.
"An issue we need to address is how to get warnings to consumers who have already bought a product believing it to be safe for them, which is subsequently recalled because of an undeclared allergen. In this case, it could have had tragic consequences."