The Fridge That Was Never Checked
A small restaurant's walk-in fridge has a digital display reading 3°C. The manager relies on the display and has not taken a manual probe reading for nine days. On Thursday a chef notices that the display has been showing 3°C continuously, even during the lunch rush when the door is open for long periods. A manual probe of a milk carton reads 9°C and a probe of cooked rice reads 10°C. The fridge was serviced six weeks ago. The restaurant serves a set lunch to 60 covers and has no record of fridge temperatures for the last nine days.
1. What is the most likely explanation for the discrepancy, and what does it mean for the food in the fridge?
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The most likely explanation is that the digital display is faulty or is showing a set point or a sensor reading that does not reflect the actual air or product temperature. A display that never moves, even when the door is open during service, is not credible as a live measurement. The manual probe readings of 9°C and 10°C are the reliable data.
The food in the fridge has therefore been stored above the safe chilled range, possibly for several days. High-risk ready-to-eat items such as the cooked rice and milk should be treated as unsafe. The rice in particular is a cooked, moist food associated with Bacillus cereus if held warm, and at 10°C it is outside safe chilled storage. The milk at 9°C is also above range.
The absence of nine days of records means the business cannot demonstrate the food was safe at any point in that period. The precautionary approach is to discard high-risk items that cannot be shown to have been kept at or below 5°C, and to have the fridge repaired and recalibrated before restocking.
2. What should the manager do immediately and what documentation should follow?
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Immediately: stop using the fridge for high-risk food, move any verified safe items to a working fridge, and discard the rice, milk, and any other high-risk items that may have been above 5°C. Notify the chef and staff, and check whether any of the affected food has already been served; if so, record it and monitor for complaints.
Call the refrigeration engineer to repair and recalibrate the unit, and verify with an independent probe before restocking. Use a calibrated probe thermometer and record air and product temperatures.
Documentation: open a temperature log showing the date, time, reading, method, and initials; record the discard with quantities and reasons; record the engineer's visit and the recalibration result; and note the corrective action. The manager should also introduce a daily manual check with a calibrated probe, a weekly calibration check, and an alarm or secondary thermometer. The nine-day gap should be recorded as a non-conformance so the cause can be addressed, and staff should be briefed that a display is not a substitute for a probe reading.