A hamburger with a metal bolt in it, a cockroach found in chips, glass in two hot beverages and a rotisserie chicken containing a maggot were among 28 Tauranga-based food safety complaints made to the Ministry of Primary Industries in the past three years.
There were four complaints last year and six as of November this year.
Some cases were referred to the product's manufacturer, others required the ministry to send an educational letter or give an official warning. Seven complaints were deemed invalid.
Bay of Plenty district medical officer of health Dr Phil Shoemack said Toi Te Ora - the region's public health service - dealt with at least one outbreak of a potential food-borne illness a week.
The illnesses were, however, often associated with events at home, or a school, hospital or rest home, rather than a food premise, he said.
"What people do in their own homes is a far bigger risk to food safety than the small but real risk of buying food from a commercial food premise," he said.
"Store food correctly, make sure your fridge is working properly, don't leave things in [the fridge] for too long, and I can't over-emphasise the importance of having clean hands before you prepare food."
Food-borne illness struck about 200,000 New Zealanders every year, according to the Ministry of Primary Industries (MPI). Nearly half of these were attributed to food handling, preparation or storage in the home.
Home food safety was a particularly big issue in summer, Dr Shoemack said.
"People tend not to pay as much attention to detail when they're cooking on the barbecue. Plan ahead, get your meat out of the freezer before you need to cook it and make sure it's cooked through."
People should raise food safety issues they had with the vendor first and then bring it to the attention of local authorities or MPI if necessary, he said.
MPI compliance operations manager Gary Orr said New Zealand had 40,000 regulated food businesses and there were serious consequences if laws, standards or rules were not met.
"MPI can suspend the operations of a business or close it down, and can also impose fines, recall food products and issue formal public communications about food safety issues to protect consumers," he said.
Consumers needed to read labels carefully, report products sold past their used-by dates and adhere to basic food safety rules at home, he said.
"If food isn't prepared and handled safely, it's easy for people to get food poisoning.
"What's more, warmer temperatures over summer provide the ideal conditions for bacteria to grow.
"Many food-borne illnesses can be avoided by remembering simple food safety practices, like washing hands before and after handling foods and thoroughly cleaning chopping boards and utensils."
MPI also urged people to refrain from buying illegal homekill meat for their Christmas roast, he said.
Homekill meat was only legal for the animal's owner, their immediate family and household, and those of their farm staff to eat.
-Food safety complaints can be passed to the MPI food safety consumer helpline on 0800 693 721.