New Zealand Food Safety is asking households to tighten up kitchen habits over the holiday period, knocking back a handful of common myths that can lead to foodborne illness.

Deputy director-general Vincent Arbuckle says many of the bugs that make people sick can’t be seen or smelled. The agency’s advice is to get leftovers into the fridge or freezer within two hours of serving — faster on hot days — in sealed containers, and reheat to piping hot (more than 75°C).

A recurring theme is temperature control. Frozen meat and other foods shouldn’t be thawed on the bench. Surface layers will warm into the 5–60°C “danger zone” while the centre remains frozen, giving bacteria a head start. Defrost in the fridge or use a microwave.

Shellfish gathered from the beach is another focus. Cooking will kill bacteria, but it will not neutralise marine biotoxins that can accumulate during algal blooms. NZ Food Safety monitors 42 recreational and 54 commercial shellfish harvesting areas; when tests exceed safe limits, public health warnings are issued and nearby aquaculture farms temporarily close. Current alerts are posted online and via signs at beaches, and are also available in MPI’s free NZ Fishing Rules app.

The agency also highlights higher listeria risk for older people and those with weakened immune systems. As immunity wanes, foods that used to be fine may no longer be safe. Higher-risk foods include deli meats and pâtés, soft cheeses, cold-smoked seafood and leafy greens. Symptoms of listeriosis in older and immunocompromised people typically appear 2–3 weeks after exposure and can include fever, muscle pain, headache, stiff neck, confusion, loss of balance and seizures. The advice: cook thoroughly, eat food soon after preparation, wash and dry fruit and vegetables well, and heat leftovers to steaming hot.

Other points NZ Food Safety wants households to apply over summer:

• Don’t rinse raw chicken. Washing spreads Campylobacter and Salmonella around the kitchen. Use separate boards and utensils for raw and ready-to-eat food, and wash hands and equipment in hot, soapy water.
• Use-by versus best-before matters. Past a use-by date, food isn’t safe to eat and can’t legally be sold. Past a best-before date, food may have lost quality but can still be safe if it looks, smells and tastes normal.
• Wash hands with soap and water. Sanitiser is a back-up; if you must use it, choose at least 60% alcohol and rub until dry.
• Raw milk carries risks from STEC, Campylobacter and Salmonella. If you choose to drink it, buy only from a registered supplier, keep it at 4°C or below, and heat to 70°C for one minute before drinking if you want to reduce risk.
• Rinse bagged salads and greens, even if labelled “washed,” particularly if preparing food for vulnerable people. Wash whole vegetables before peeling to avoid transferring contaminants.
• The “five-second rule” is a myth. Once food hits the floor, contamination is possible. If it’s salvageable, rinse and cook thoroughly.
• Don’t scrape off mould and carry on. Filaments and spores can penetrate beyond what you see, and some moulds produce mycotoxins. Discard mouldy food.
• Health Star Ratings compare like with like. Use the stars to choose between similar products (e.g., two cereals), not to compare different categories.

NZ Food Safety’s release notes that specific “how long in the fridge” guidance varies by food type; its core message is to cool quickly, store covered and cold, and reheat hot.

Up-to-date shellfish biotoxin alerts and food safety resources are available on MPI’s website and in the NZ Fishing Rules app. For advice or concerns, contact MPI on 0800 008 333 or media@mpi.govt.nz.