Reheating, Food Safety Glossary

Rapidly heating previously cooked and cooled food back to at least 60 degrees C so it is safe to hot hold or serve. Reheating is warming food that has already been cooked and then cooled or refrigerated, so it can be served hot again. Because the food passes back through the temperature danger zone during reheating, it needs to move through that range quickly to limit the time bacteria have to grow. Slow reheating, such as gently warming food over a long period, can keep it in the danger zone for too long and is unsafe. The Australia New Zealand Food Standards Code approach is that food being reheated for hot holding should be brought rapidly to at least 60 degrees C. Reheating equipment such as ovens, stovetops and microwaves is suited to this because it heats quickly, whereas hot holding equipment like a bain-marie is designed to keep hot food hot, not to reheat cold food. Once reheated to 60 degrees C, the food can be held hot at or above that temperature. In an Australian kitchen this means using a stove, oven or microwave to reheat food quickly to at least 60 degrees C, then transferring it to hot holding, rather than trying to reheat cold food in the bain-marie. Staff check the core temperature with a probe thermometer to confirm 60 degrees C has been reached, especially in the centre and thickest parts of the food. Reheating is generally intended to be done once. Repeatedly cooling and reheating the same food increases the time it spends in the danger zone and the risk of contamination, so businesses usually reheat only the amount they expect to use. Reheating temperatures are often recorded as a monitoring step in the food safety program. A function centre reheats a tray of lasagne cooked the day before. Staff place it in the oven rather than the bain-marie, then probe the centre to confirm it has reached at least 60 degrees C throughout before moving it to hot holding at or above 60 degrees C for service.