Chiller failure overnight at a suburban café
At 6:45am on a Saturday, the duty cook at a 40-seat suburban café opens the walk-in chiller and the display reads 11.2°C. The last logged check was Friday at 4:00pm, 3.1°C. No one was on site overnight, the kitchen was about 19°C, and the compressor has tripped its breaker. Inside are 8L of opened milk (best before Tuesday), 3kg of cooked sliced ham with a use-by of today, 2kg of raw chicken breast (use-by tomorrow), 4kg of unopened hard cheese, 6kg of bagged salad mix, 2kg of in-house aioli made on Thursday, and two tubs of cut fruit. Service starts at 8:00am with 60 lunch bookings, and the owner is not answering the phone. A colleague says the ham smells fine and the chicken will be cooked anyway, so 'nothing needs to be thrown out'. The breaker is easily reset, and the chiller drops to 3°C within 40 minutes.
1. What do you do with the food before the 8:00am service, and why?
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Decision: do not sell any of it, and do not judge by smell.
- The chiller was last verified at 3.1°C at 4:00pm Friday. It is now 6:45am Saturday. That is up to about 15 hours with no record, and the display reads 11.2°C. You cannot show how long the food was above 4°C, so you must assume the worst case: more than 4 hours in the danger zone (5–60°C).
- Under the 2-hour/4-hour approach used in NZ temperature-control guidance, ready-to-eat potentially hazardous food that may have been above 4°C for more than 4 hours must be discarded. That covers the milk, ham, aioli, cut fruit and salad mix.
- Smell is not evidence. Staphylococcus aureus and Bacillus cereus toxins, and Listeria, can be present in food that looks and smells normal, and toxins are not destroyed by reheating.
- Raw chicken: it will be cooked to 75°C, but it has still spent hours at warm temperature and you cannot demonstrate it was safe. Discard it rather than build the lunch service on it.
- Unopened hard cheese is lower risk, but you still cannot show time and temperature, so the defensible call is to discard or hold it aside as 'do not use' until the owner decides.
- Segregate and label everything 'DO NOT USE', photograph the display, and list weights so the loss can be recorded.
2. A colleague argues: 'Cook the chicken to 75°C and it will be fine - heat kills everything.' How do you respond?
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Say no, and explain why the 'it gets cooked' argument fails.
Cooking chicken to 75°C kills bacteria such as Salmonella and Campylobacter, but it does not destroy heat-stable toxins that bacteria may already have produced while the meat sat at 11–19°C overnight, for example S. aureus toxin. It also does not remove the cross-contamination risk of handling a large amount of warm raw chicken during a busy service.
More importantly, you cannot show the food was safe. Under the Food Act 2014 you must sell food that is safe and suitable, and if something went wrong you would have no evidence supporting the decision to cook and sell it. 'It will be fine' is not a record.
Practical alternatives: ring the supplier or another store for fresh chicken, change the menu to dishes that do not need chicken, and tell booked customers if needed. Keep the discarded chicken separate, record the weight, and do not let it back into the kitchen. If you did have a written record showing less than 2 hours above 4°C, you could cook and sell immediately - but here you have no such record.
3. What corrective actions and records do you complete, who do you notify, and what changes so this does not repeat?
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Corrective actions, records and prevention
- Reset the breaker, then confirm the chiller pulls down to 4°C or below and holds it for at least an hour before restocking. Do not restock a chiller that has not proved it works.
- Book a refrigeration technician; check the door seals, the condenser and the breaker load.
- Check the thermometer is working with an ice-point check (0°C in an ice slurry) and record the result.
- Record the incident: time found, display temperature, last verified check, list and weight of discarded food, action taken, who was notified.
- Notify the owner/manager and the insurer; keep receipts for replacement stock.
- Review the menu for the day and source replacement food from a supplier that can provide temperature records.
- Prevention: fit a temperature data logger or alarm, label the breaker, do an opening check every day, write an after-hours plan, train staff, and avoid overloading the chiller so it recovers quickly after deliveries.