GIFSQ Tools · Module 17 — Food Processing, Thermal Engineering & Utilities · Tool 323 of 500
Check a pasteurisation hold against its scheduled time and temperature, work out the F-value delivered at the target temperature, and keep a run log saved on this device.
Try sample values — fills the form with the worked example below.
Saved on this device only.
| Batch | Hold | F (min) | Margin (%) |
|---|---|---|---|
| No runs saved yet. | |||
–
F delivered (min)
–
F required (min)
–
Margin (%)
Equation: F = (hold time in minutes) × 10^((hold temperature − scheduled temperature) / z); margin (%) = (F − required) ÷ required × 100.
Method: Bigelow F-value method applied to a pasteurisation hold, per FDA 21 CFR 113/114 thermal processing practice and IFT guidance; the log records each run for traceability.
Assumptions: the hold temperature is the lowest temperature seen during the hold; a single z-value applies; the scheduled time and temperature are those in the approved scheduled process.
Limitations: a single hold reading cannot replace continuous chart or data-logger records; a failed run must be dispositioned under the plant procedure, not by this tool alone.
Rounding: F-values to 3 decimal places, margin to 1; intermediates unrounded.
This is a calculation aid, not a laboratory report — confirm against your accredited method before citing a value. A calculated lethality is an estimate only — a scheduled process must be established by a qualified process authority; never present this calculation as a validated process.
Method: Bigelow F-value method applied to a pasteurisation hold, per FDA 21 CFR 113/114 thermal processing practice and IFT guidance; the log records each run for traceability.
Assumptions: the hold temperature is the lowest temperature seen during the hold; a single z-value applies; the scheduled time and temperature are those in the approved scheduled process.
Limitations: a single hold reading cannot replace continuous chart or data-logger records; a failed run must be dispositioned under the plant procedure, not by this tool alone.
Rounding: F-values to 3 decimal places, margin to 1; intermediates unrounded.
This is a calculation aid, not a laboratory report — confirm against your accredited method before citing a value. A calculated lethality is an estimate only — a scheduled process must be established by a qualified process authority; never present this calculation as a validated process.
Worked example: Milk held at 72 °C for 15 s against a 71.7 °C / 15 s schedule with z = 7.5 °C: F = 0.274 min against 0.250 min required, margin +9.6%.
Enter values above to see results.
HTST milk pasteurisation is 71.7 °C for 15 s; your product schedule may differ. Runs are saved on this device only. Tool 323 of 500 — GIFSQ
