Temperature control and cold chain

If you could only control one thing in a kitchen to keep food safe, it would be temperature. Most foodborne illnesses are caused by bacteria that have been allowed to multiply because food has been kept too warm or too cool for too long. Temperature control is therefore the core of both self-check and HACCP — and it is something you can measure, document and prove.

§The warm zone

Bacteria Multiply Fastest in a Lukewarm Temperature Range — Roughly Between Fridge-Cold and Smoking Hot. The Longer Food Spends in This Zone the More Bacteria Grow. The Principle in All Temperature Control is Therefore Simple: Keep Cold Food Really Cold, Keep Hot Food Really Hot, and Get Food as Quickly as Possible Through the Lukewarm Zone — Both on the Way Up and on the Way Down.

§The cold chain — uninterrupted from receipt to use

The cold chain is the unbroken series of cool links a refrigerated product must go through from the supplier until it ends up on your plate. Break the chain just once — goods stand too long at the loading dock, the fridge is overfull, or a tray is forgotten on the table — the damage is done, even if the rest of the chain is perfect. Take the temperature on receipt and get refrigerated goods on cold without unnecessary delay.

• 01Receive and check the temperature of chilled and frozen goods upon delivery.
• 02Get cold products on ice immediately — don't let them stand and get warm.
• 03Do not overfill refrigerators; air must be able to circulate and maintain temperature.
• 04Only take out what you need now and return the rest quickly.
• 05Keep track of how long a product has been out of the cooler during preparation.

§Cooling — the critical point many overlook

Prepared food that needs to be stored must be cooled quickly through the lukewarm zone. If you leave a large pot to steam on the kitchen bench, the cooling takes too long and bacteria get free rein. Divide large portions into smaller ones, use a blast chiller or ice bath, and don't leave the container closed while it is still warm. Cooling is a classic critical control point in HACCP.

§Reheating and hot holding

When cooked food is reheated, it must be brought quickly and thoroughly to a warm temperature—not just on the surface. Held hot food must be kept thoroughly warm throughout service; if it stands and becomes lukewarm, it wanders back into the danger zone. Never reheat the same portion multiple times, and discard food that's been standing too long.

§Measure and document rather than guessing

Temperature cannot be estimated with your finger — it must be measured. Use a clean, calibrated thermometer, measure the core not just the surface, and clean the probe between raw and cooked so you don't transfer bacteria yourself. Note the measurements in the self-inspection; documentation is both your proof to the inspector and your own guideline for following routines.