In canned food production, high-temperature sterilization is a critical process to ensure product safety and extend shelf life. A typical sterilization cycle involves heating sealed cans in a pressurized retort (sterilization kettle) to eliminate harmful microorganisms while preserving food quality. Precise control over temperature, pressure, and sterilization time is essential—not only for food safety compliance but also for maintaining consistent taste, texture, and nutritional value.
For this automation case, the sterilization process is managed using the following hardware and software setup:
Main Controller: ARMxy Edge Controller running OpenPLC for process automation logic.
Analog Input Board (Y-AI): Monitors real-time temperature and pressure inside the retort.
Digital Output Board (X-DO): Controls steam inlet valves and drain valves for process regulation.
The Y-AI board continuously collects critical process variables:
Sterilization temperature: 0–150 °C range, ensuring accurate monitoring through high-precision sensors.
Internal pressure: 0–0.6 MPa range, maintaining safe and effective sterilization conditions.
The F-value (sterilization value) is a key parameter that measures the accumulated lethality of the sterilization process. By integrating F-value calculation into the PLC program, the system:
Adjusts steam valve operation to maintain the optimal temperature profile.
Automatically regulates sterilization time based on the target F-value.
Minimizes human error and ensures consistent product safety.
The system automatically generates detailed sterilization cycle reports, including:
Temperature and pressure curves over time.
Calculated F-values for each batch.
Cycle start/end timestamps and operator logs.
These records comply with FDA electronic records requirements, making them suitable for audit and regulatory verification.
Consistent Quality Control: Automated temperature and pressure control ensures every batch meets safety and quality standards.
Remote Access to Historical Data: Quality control teams can review past sterilization curves and reports without needing physical access to the plant.
Regulatory Compliance: Electronic records are securely stored, traceable, and meet FDA 21 CFR Part 11 standards for data integrity.
Operational Efficiency: Automated adjustments reduce manual intervention, saving labor and minimizing process deviations.
Data-Driven Optimization: Long-term process data supports trend analysis, helping optimize steam usage and cycle times for energy savings.
By integrating OpenPLC with the ARMxy industrial controller and modular I/O boards, food processing plants can achieve precise, automated control of retort sterilization processes. This approach not only ensures compliance with stringent safety regulations but also enhances production efficiency and quality consistency—making it an ideal solution for modern canned food manufacturing.
