Combining a deflection logger and a pressure logger inside an autoclave during the sterilization of food packages allows for comprehensive monitoring and validation of the process, especially when working with flexible or semi-rigid packaging (like pouches, trays, or cans). Here’s why each logger is used, and why using both together is important:
1) Pressure data logger
- Purpose: Measures the internal pressure inside the autoclave chamber during sterilization, but also inside the different packaging. One or two pressure loggers can be used simultaneously to optimize the process analysis.
- Importance:
o Ensures that the correct pressure is maintained for steam saturation and microbial destruction.
o Measure the differential pressure applied to the packaging
Helps validate the sterilization cycle by confirming that conditions stayed within the required thresholds.
2) Deformation data logger
- Purpose: Measures physical deformation (deflection) of the food package (e.g., expansion or contraction of flexible packaging).
- Importance:
o Monitors how the package reacts to pressure and temperature changes.
o Prevents package rupture or paneling (permanent deformation from pressure balance).
Ensures package integrity is maintained—critical for shelf life, safety, and appearance.
Why combine both ?
- Pressure alone isn’t enough: Even if the chamber pressure is correct, the package could still deform or burst if internal vapor pressure isn't balanced properly.
- Deflection alone isn’t enough: If a deflection occurs, but you don’t know the pressure conditions that caused it, it’s hard to optimize or troubleshoot the process.
• Together, these loggers help you:
- Correlate pressure conditions with package behavior.
- Design sterilization cycles that are effective (kill pathogens) and gentle (maintain package integrity).
- Validate and document compliance with regulatory standards (e.g. FDA, EU food safety).
- Optimize overpressure monitoring (back pressure) to match package needs.
- Avoid air trapped inside the chamber (which reduces sterilization efficiency).
- Figure out if the steam wasn't fully saturated.
- Know if the pressure sensor in chamber if fully functional and representative of load conditions.
In brief :
Using both a deflection logger and a pressure logger gives a complete picture of what's happening during sterilization—inside the chamber and to the package. This is critical for ensuring that the food is safely sterilized without compromising the packaging.
Of course, these loggers are used in addition to temperature loggers to ensure the right sterilization process.