The challenge
Listeria monocytogenes actively grows at refrigeration temperatures (0–10 °C) and therefore poses a particular risk to products that consumers do not reheat. EU Regulation 2073/2005 requires manufacturers to demonstrate that their HACCP system actively controls this risk. Current practice—manual core temperature measurements on a random basis, typically three to five per shift—provides coverage of approximately 11% of production. While this is formally compliant, it does not provide demonstrable 100% monitoring per product.
The consequences of an incident are far-reaching: recalls cost an average of €5M to €50M, an NVWA production stop can last for months, and reputational damage can have long-term effects spanning years. Furthermore, a hand thermometer typically measures core temperature – not the surface temperature per compartment, which is crucial for preservation and shelf life.
The manufacturer was looking for a solution that offers 100% coverage, integrates seamlessly with the existing line, and provides a complete digital audit trail for IFS/BRC certification and NVWA inspections.
The solution
Vision Partners developed and installed a turn-key inline thermal inspection system that monitors the heat profile of every meal tray immediately after the packaging process. The system non-contact measures the surface temperature of the film surface and automatically converts that measurement via a thermal 4-layer model to the expected food surface temperature per compartment—without process interruption.
The system consists of:
- Industrial thermal camera (IP66) — measures the infrared profile of each package in real-time, completely contactlessly
- Blackbody temperature reference — Ensures continuous, traceable calibration of the camera in the production environment
- Thermal 4-layer model automatically calculates the correction from foil temperature to food surface temperature; the operator selects the active product, the rest proceeds automatically
- RVS image acquisition tunnel — Shielded measuring point above the conveyor belt, custom-mounted per line
- Inspection Dashboard — Real-time temperature monitoring, historical log with over 10,000 inspections, HACCP export report (PDF/CSV), and automatic alarm upon threshold breach
- PLC connection via OPC-UA / Ethernet — direct integration with existing line control; OK/NOK signal per package, with optional rejection facility
- Cloud data upload — meetdata available outside the production floor for analysis and audit trail
Vision Partners delivered the system as a complete turn-key solution: from 3D design drawings and electrical design to on-site commissioning, operator training, and user manuals. An annual service and maintenance subscription includes emergency service, software updates, an annual on-site system verification, and a helpdesk.
The result
Whereas previously approximately 11% of production was checked via manual spot checks, the system now monitors every single tray—without causing any line delays and without requiring any additional operator intervention. Each measurement is recorded in a digital log that can be exported directly as an HACCP report for audits and certifications (IFS, BRC, NVWA).
The system automatically detects products that do not meet the minimum temperature threshold and immediately triggers an alarm—or sends a reject signal to the line. This demonstrably ensures food safety, cycle after cycle.
An additional advantage is the ability to fine-tune the pasteurization process more precisely. Because the system provides exact insight into the temperature achieved per compartment, the producer no longer needs to build in a safety margin by heating products longer or hotter than necessary. The result: lower energy consumption per production cycle and a better product taste because over-processing is avoided.
For the manufacturer, the system offers immediate benefits: food safety assurance for each product, full digital traceability, a demonstrable reduction in the risk of Listeria, a reduction in waste and the risk of recalls, and less over-processing. Vision Partners managed the entire process—from initial research and proof-of-concept to FAT, SAT, and delivery—and guarantees continuity through a multi-year service contract.
Want to learn more about inline thermal inspection for your production line? Get in touch.
