Cooking, Cooling and Reheating
This domain tests the process controls that make food safe from the pan to the plate: achieving a lethal core temperature, cooling rapidly, holding hot, and reheating correctly. Questions often use a scenario with a large joint, a curry cooked the day before, or a rice dish, and ask what the handler should have done differently.
Cooking
Heat must reach the centre or thickest part. The benchmark is 75 °C for 30 seconds or an equivalent time/temperature combination. Whole cuts of beef or lamb may be served pink, but minced meat, rolled joints, poultry and any dish containing them must be cooked through. Stir food during cooking so all parts reach temperature. Probe, then disinfect the probe.
Cooling
Given a large pot of stew at 63 °C, the target is 8 °C within 90 minutes. Methods:
- Decant into shallow containers no more than about 5 cm deep.
- Use an ice bath or cold water bath with stirring.
- Use a blast chiller.
- Divide large batches into smaller portions.
- Do not place hot food in a fridge if it would raise the fridge temperature; cool first, then refrigerate.
Hot holding and reheating
Hold hot food at 63 °C or above, using a bain-marie or hot cupboard, and check the food temperature rather than the water. Reheat to 82 °C and reheat only once. Never reheat in a bain-marie; use a hob, oven or microwave and then transfer. Stir to remove cold spots and let microwaved food stand.
Worked example
A caterer cooks 30 litres of chicken curry at 4 pm, leaves it covered on the hob, and refrigerates it at 9 pm. The next day it is reheated in a bain-marie to 70 °C and served. Reasoning: the curry sat for five hours in the danger zone, allowing Clostridium perfringens spores to germinate and multiply; cooling took far longer than 90 minutes. The reheating temperature of 70 °C is below the 82 °C standard, and the bain-marie is the wrong appliance. Correct approach: decant into shallow trays, cool to 8 °C within 90 minutes, refrigerate, then reheat once to 82 °C on the hob.
Traps that cost marks
- Reheating to 75 °C because it is the cooking figure.
- Cooling at room temperature overnight and believing a fridge will fix it.
- Reheating more than once, or reheating in hot-holding equipment.
- Measuring the bain-marie water temperature rather than the food.
- Cooking rolled or minced meat rare.