A probe left in the cooling food stamps the moment it passes 60, 21 and 5 °C. Callisto times both stages, raises an alert if one runs late, and keeps the curve with the batch on the cooldown list.
Cooked food has to pass through the danger zone quickly. Callisto measures it instead of trusting a clipboard.
The two-stage rule, built in
Below 21 °C within 2 hours, then below 5 °C within a further 4 hours: the cooldown list checks every batch against both stages.
Start, mid and end checks
The Cooldown Device’s K-type probe stays in the food and stamps the start, mid and end of each run, showing the stage on its own screen.
Timeouts raise alerts
If a stage runs past its limit, a mid- or end-stage timeout alert goes to the people set up for cooldown alerts.
The cooldown list
Every batch with its start and end, cooldown type, use-by and expiry dates and its cooling graph, including compound dishes made from several parts.
Manual cooldowns too
On the handheld, two-stage timers (2 h and 4 h by default, editable) keep running through app restarts, and each run ends as complete, timed out or cancelled.
Calibrated probes
Ice-point and boiling-point checks are recorded for the probes, so the readings behind each cooldown can be trusted.
Cooldown list Beef ragu · complete in 3:29 · use by +72 hRecorded
Illustrative cooldown · sample data
01
Probe in
Step 1: The clock starts at 60 °C.
The dish is picked from your menu and the Cooldown Device’s probe goes into the food. The moment the core passes 60 °C, stage one starts and the time is stamped.
02
Stage one · 2 hours
Step 2: Below 21 °C within 2 hours.
Callisto counts down the first stage and stamps the moment the food reaches 21 °C. If it is still above 21 °C when the time is up, a timeout alert goes out.
03
Stage two · 4 hours more
Step 3: Below 5 °C within 4 more.
A second clock starts at 21 °C, and the device shows the stage on its own screen. The end check is stamped the moment the food reaches 5 °C.
04
On the record
Step 4: Straight onto the cooldown list.
The run is filed with its curve, its start, mid and end times and a use-by date, ready for the HACCP report.
The device in the food
Meet the Cooldown Device.
The Cooldown Device sits in the cooling food with its thermocouple probe, shows the stage on its screen, and records the cooldown from first reading to last, raising an alert if a stage runs late.
MeasuresFood core temperature with a K-type thermocouple probe
DisplayOn-device screen showing the cooling stage
Connects byLoRaWAN via the CT Gateway
Dish namesPicked from your menu, sent from the platform
CalibrationIce-point and boiling-point checks on the device
The two-stage rule: from 60 °C to below 21 °C within 2 hours, then to below 5 °C within a further 4 hours. These are the cooling limits set out in the Australia New Zealand Food Standards Code.
What happens if a stage runs late?
A timeout alert is raised for that stage and sent to the people set up for cooldown alerts, and the run is recorded as timed out.
Can we record a cooldown without the Cooldown Device?
Yes. The handheld runs two-stage timers, 2 hours and 4 hours by default and editable, that keep running if the app restarts. For sites without LoRaWAN coverage there is the C04 Wi-Fi Cooldown Device.
What about dishes made from several cooked parts?
The cooldown list supports compound dishes, so each part’s cooldown is recorded against the dish it goes into.
How is the use-by date set?
The cooldown list gives each recorded batch a use-by date 72 hours ahead, shown with the batch.
