Blast chilling in the kitchen: when, how, and what to record

A cooked food that lingers in the so-called temperature danger zone is a favourable ground for microbial growth, no matter how careful the cooking was. Blast chilling exists specifically to cut down the time spent in that range.

Why blast chill instead of cooling at room temperature

Leaving a pan to cool on the counter means crossing the danger zone slowly and unpredictably, with timing that depends on the season, the batch size and the kitchen temperature. A blast chiller makes that step fast, repeatable and measurable.

When it's needed

• Cooked preparations meant for storage, not immediate consumption
• Products to be portioned or packed after cooking
• Batch-prepared items made ahead for later services
• Products destined for freezing, where negative blast chilling limits large ice crystal formation

The two cooling curves

Positive blast chilling brings the product to refrigeration temperature quickly, typically within a couple of hours of the end of cooking. Negative blast chilling, used for freezing, pushes the product to much lower temperatures within a similarly short window, preserving texture and quality as well as safety.

What to record

1. Product chilled and quantity
2. Starting temperature at the end of cooking
3. Final temperature reached and time taken
4. Cycle or programme used
5. Date and time, with who carried out the operation
6. Where the product went afterwards (fridge, freezer, portioning)

Common mistakes without a blast chiller

• Covering the pan while still hot, slowing down heat dissipation
• Putting large hot volumes straight into the fridge, raising the temperature of the whole unit
• Not splitting the product into shallower, wider containers to speed up cooling
• Calling something "cooled" just because it no longer feels hot, without actually measuring it