Cooling the Curry Overnight
A takeaway cooks a 20 kg batch of chicken curry at 9 p.m. The pot is left on the gas ring to cool, covered, and the kitchen is locked at 10 p.m. At 11 a.m. the next day, the curry is reheated in the same pot until it is 'steaming', then transferred to a hot-holding unit at 58°C for the lunch trade. Thirty portions are sold between 12 and 2 p.m. The rice was cooked at 10 a.m. and left in a warm cupboard until service. The owner says the curry 'smells fine' and has been doing this for years without complaints. Two customers telephone the next day to say they had vomiting and diarrhoea about 8 hours after eating. The takeaway has no written HACCP plan, no temperature records, and one probe thermometer with a flat battery. The local environmental health officer is due for a routine inspection next week.
1. Identify the likely food safety failures and the organisms most likely involved, with reasoning.
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Cooling failure. A 20 kg pot left at room temperature overnight cools very slowly. That is a classic risk for Clostridium perfringens: spores survive cooking, germinate during slow cooling, and can cause illness after about 8 to 22 hours. Reheating may kill vegetative cells but does not reliably destroy spores or toxin already formed. The customers' 8-hour incubation and diarrhoea fit this pattern.
Rice risk. Cooked rice left in a warm cupboard is a Bacillus cereus risk. The emetic toxin is heat-stable, so reheating does not make it safe. Hot holding at 58°C is below the 63°C minimum, allowing bacteria to grow. The lack of records, HACCP plan and a working probe shows the business cannot demonstrate control.
2. What should the owner do now about the remaining food and the complaints?
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Stop selling and discard. The remaining curry and rice should be taken out of sale and discarded. Smell is not a reliable safety test. Do not recook and sell the curry in an attempt to fix it; heat-stable toxins and spores may remain.
Investigate and communicate. Record what was sold, when and to whom, and cooperate with the environmental health officer and any outbreak investigation. Advise affected customers to seek medical advice and report the matter to the local authority. Clean and disinfect the area, check the probe thermometer and calibration, and review staff health. The owner should not argue that years without complaints prove the method is safe; absence of reported illness is not evidence of control.
3. What HACCP-based controls and records must be put in place before the inspection?
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Identify control points. Treat cooking, cooling, hot holding and rice handling as critical controls. Set measurable limits: cook poultry to at least 75°C; cool from 63°C to 8°C within 90 minutes, or use a validated equivalent such as shallow trays and rapid chilling; hot hold at 63°C or above; reheat to 75°C or above.
Monitor and correct. Use a calibrated probe, record temperatures at the required frequency, and define corrective actions such as discarding, recooking or extending cooling only within a validated procedure. Verify records and review the plan when the menu changes. Train staff and keep the records available for the inspection. A documented HACCP system supports due diligence, but only if staff actually follow it.