Forty-Five Litres of Stew in a Church Kitchen With One Reach-In
Sunday, 22:30. A church hall kitchen has finished a fundraising dinner. Eighty litres of beef-and-barley stew were cooked and served, and 45 L are left over. The equipment is one reach-in cooler at 3 °C, one ice machine, no blast chiller, and the volunteers have already gone home. A helper ladles the stew into three stockpots 40 cm deep, puts the lids on while the stew is still hot, and slides all three into the cooler next to a tray of raw chicken for Tuesday. Monday 07:00, a probe at the centre of one pot reads 14 °C; near the wall of the pot it reads 8 °C. The pot is still warm to the touch. The coordinator wants to "boil it hard for 20 minutes" and serve it at the 11:30 lunch for ten people, and it is also booked for a seniors' lunch on Tuesday. No cooling temperatures were recorded overnight.
1. Is the stew safe to reheat and serve? Answer using the cooling limits and explain what boiling can and cannot fix.
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No. The stew failed cooling by a wide margin.
The standard two-stage limit is: 60 °C to 20 °C within 2 hours, then 20 °C to 4 °C within 4 hours, for a total of 6 hours. Here the stew went into the cooler at about 22:30 and was still at 14 °C at the centre 8.5 hours later. It was in the danger zone for hours beyond the limit, in a deep, tightly lidded, anaerobic pot - precisely the conditions Clostridium perfringens favours, with Bacillus cereus as a secondary concern in a starch-containing stew.
Boiling for 20 minutes kills vegetative bacteria but not heat-stable toxins. It also does nothing about the spores that have already formed. Serving it would move the risk from "uncertain" to "known hazard" while giving everyone the false comfort of a hard boil.
Decision: discard all 45 L, document the quantity and the readings, and do not use the stew for the Tuesday seniors' lunch. If the coordinator insists, the person in charge must be the one who refuses, in writing.
2. What should have been done Sunday night with only a reach-in, ice and time? Give a method that actually meets the two-stage limits.
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The goal is to maximise surface area and move heat out fast:
- Divide before cooling. Portion into shallow pans no more than 5 cm (2 in) deep - roughly 15–20 pans rather than 3 pots. A 40 cm pot is effectively an insulator.
- Use the ice bath. Set pans in a sink or tub of ice and water, stir every 15 minutes, and replenish ice. Stirring breaks the warm boundary layer; a still pot cools at a fraction of the rate.
- Or use an ice paddle filled with ice and stirred through the stew, which cools from the inside out.
- Vent, don't lid. Leave lids loose or off in the cooler so heat escapes; stacking hot pans or putting them beside raw chicken is a cross-contamination risk and slows cooling.
- Separate raw from cooked - raw chicken should never share a shelf above or beside cooling ready-to-eat food.
- Monitor to a schedule: probe the centre at 2 hours (target ≤20 °C) and at 6 hours (target ≤4 °C), write the numbers down, and calibrate the probe.
- Reduce the batch. Cooking 80 L for a dinner of that size and then trying to cool 45 L in a domestic kitchen is a planning failure; cook to forecast or freeze in small portions immediately.
3. Write the corrective action for Monday morning and the three elements you would put in a written cooling procedure for volunteers.
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Corrective action record (Monday 07:00): product - beef-barley stew, 45 L; cooling start 22:30; readings 14 °C centre / 8 °C edge at 07:00; limit breached (should be ≤4 °C at 6 hours); action - discarded, photographed, witnessed by the coordinator, quantity noted; root cause - deep pots, lidded hot, no ice bath, no monitoring, single overloaded cooler; preventive action - shallow pans purchased, ice paddle purchased, written procedure posted, volunteers trained before the next event.
Also review whether any stew was served Sunday night after cooling had started; if so, log it and notify the local health authority if anyone reports illness.
Written procedure should contain:
- Critical limits - 60→20 °C in 2 hours, 20→4 °C in 4 hours, with the pan depth and method stated.
- Monitoring - who probes, where (centre of the thickest part), at what times (2 h and 6 h), and where the numbers are recorded and kept.
- Corrective action - if the 2-hour limit is missed, you may actively continue cooling and re-check; if the 6-hour limit is missed, discard. No exceptions, no boiling.
Add training sign-off and a rule that no pot deeper than 5 cm is used for leftovers.