Food Safety Matters – Episode Summary

Episode Title

FlexXray: Emerging Technologies for Improving Foreign Material Detection
Date: March 17, 2026
Host: Adrienne Blum (Editorial Director, Food Safety Magazine)
Guest: Kai Luker (Leader of Inspection Technology, FlexXray)

Episode Overview

In this special episode, the Food Safety Matters team dives into the persistent challenge of foreign material contamination in food manufacturing—a top cause of food recalls and an ongoing worry for producers and food safety professionals. Host Adrienne Blum speaks with Kai Luker of FlexXray, exploring why foreign material detection remains so difficult despite new technologies, and how advanced innovations like computed tomography (CT) and AI-driven algorithms are changing the landscape of food safety inspection.

Key Discussion Points and Insights

1. Why Foreign Material Contamination Remains Challenging

• Difficulty Detecting Certain Materials:
  Foreign materials like bag liners, glove tips, and especially wood are difficult for conventional detection systems to find.

  "Some of these things that we deal with in a food plant are just extremely difficult to detect, especially if we're waiting until the end of the manufacturing line with the metal detector or an X-ray." (Kai Luker, 02:19)

• Reliance on End-of-Line Detection:
  Most strategies focus on detecting foreign material at the end of the process, rather than a holistic approach that includes supplier controls or upstream checks.
• Reactive, Not Proactive Mindset:
  Inspection technologies are mostly “signaling devices” rather than preventive or mitigating solutions.

  "For foreign material, it's kind of a wait and react...we continue to be in this reactionary place." (Kai Luker, 02:58)

2. The Role and Limitations of In-House Reinspection

• Financial Considerations:
  Companies invest in expensive detection equipment and want to maximize its use by reinspecting in-house.
• Ineffectiveness of Repeating the Same Process:
  Reinspecting with the same technology and settings rarely yields better results.

  "Essentially we're reinspecting that product with the same technology at the same speeds and the same standards that we did the first time... we're just doing the same thing over and over." (Kai Luker, 05:49)

3. Why and When to Use a Third-Party Inspection Partner

• Expertise and Specialization:
  FlexXray teams specialize in foreign material inspection. In contrast, internal teams are usually focused on manufacturing, not on fine-tuned inspection.
• Superior Technology and Process:
  FlexXray uses medical-grade X-ray devices—like those found in heart cath labs—operating at much slower speeds, which greatly enhances image quality and sensitivity for finding small or difficult contaminants.

  "Our instruments at FlexXray are more medical based... we're slowing that down to 5ft or less whenever we do an inspection at FlexXray." (Kai Luker, 09:05)

4. FlexXray's Computed Tomography (CT) Technology

• Transformational Capabilities:
  CT allows for automated, three-dimensional inspection, slicing the product into half-millimeter slices on three axes (X, Y, Z). This method eliminates issues with product layering and reveals contaminants that 2D X-ray can miss.

  "We're slicing that product into half millimeter slices and evaluating the reconstruction of those images on three planes...and then also look at the adjacent slice data to create volumetric data around the foreign object." (Kai Luker, 10:43)

• Real-World Impact:
  CT has helped FlexXray achieve sub-3 mm detection levels for challenging materials like gaskets and rubber, and it is now present in nearly all FlexXray US facilities.

5. Commitment to Technology Innovation and Collaboration

• Philosophy:
  Foreign material safety is not a competitive space; FlexXray is open to collaborating, including with academic partners and firms using microwave- and hyperspectral-based detection systems for different product types.
• Sample Testing and Data Driven Approach:
  Every new inspection job begins with rigorous sample testing to determine the smallest piece detectable in real product conditions—aiming for worst-case scenarios and rejecting cases where detection isn't reliable.

6. Best Practices for Working With an Inspection Partner

• Rigorous Quality Programs:
  Clients should ensure that third-party inspection partners have mirrored quality systems, robust GMPs, are certified (e.g., BRC, USDA V status, FDA registered), and treat food with the same standard as internal teams.

  "It might seem like a basic fundamental requirement, but it is something to ensure that you're doing your due diligence...you definitely want to make sure that they're going to handle everything the right way." (Kai Luker, 16:40)

7. Future of Detection Technologies

• Photon Counting Technology:
  The most promising new development is inline X-ray with photon counting detectors, which create clearer images and can discriminate foreign materials by energy type, potentially turning X-rays from basic detection tools into precise measurement devices.

  "The biggest win is going to be in using a multi pronged approach...microwave upstream or hyperspectral imaging upstream and then photon counting downstream." (Kai Luker, 19:48)

• Algorithmic Advancements with AI:
  FlexXray is leveraging machine learning and AI to build sophisticated image analysis, such as segmentation (detecting material inside containers by ignoring expected features).

  "One of the first algorithms...is called segmentation...identify the glass of the container, identify the metal lid...inspect a multi-pack at one time and only look inside of those containers to discern foreign material." (Kai Luker, 21:08)

Notable Quotes & Memorable Moments

• On the challenges of foreign material detection

  "We're really not holding our suppliers internally or externally, to these testing standards...we continue to be in this reactionary place that we continue to be in as it relates to foreign material."
  — Kai Luker [02:50]

• On the value of third-party inspection

  "As a manufacturer, we are geared to make products and do that well. We're not necessarily adept at reinspecting. And in fact, as we've shifted from metal detection to X Ray...we're reliant more so on external vendors and partners to help us do that."
  — Kai Luker [06:58]

• On the breakthrough of CT technology

  "For the first time we can understand the size and orientation of the object within the product matrix. That's huge."
  — Kai Luker [11:04]

• On adoption of new tech

  "The biggest win is going to be in using a multi-pronged approach...when we couple these things together, we're just building the best defense system that we can for foreign material overall."
  — Kai Luker [19:57]

• On future inspection capabilities

  "For me personally, I'm most excited about continuing to leverage CT technology. We're really just at the forefront of that at the moment."
  — Kai Luker [22:05]

Important Timestamps

• [02:13] — Why is foreign material still so hard to detect?
• [04:10] — The role of FlexXray as an external inspection partner
• [05:49] — Limitations of reinspecting with the same equipment in-house
• [08:46] — FlexXray’s unique inspection capabilities (2D medical X-ray versus typical inline)
• [10:20] — What CT technology is, and how it revolutionizes detection
• [13:35] — FlexXray’s approach to evaluating and piloting new inspection technologies
• [15:10] — Step-by-step: How food manufacturers work with FlexXray
• [17:49] — The future of detection: photon counting and multipronged technology
• [20:22] — FlexXray’s most exciting new developments, including AI-driven segmentation

Final Thoughts

This episode offers a comprehensive look at why foreign material detection remains a top challenge and how both mindset and technology must evolve. Listeners walk away with a clearer sense of the limitations of traditional approaches, the strategic value of advanced methods like CT and photon counting, and best practices for leveraging a qualified inspection partner. The conversation also highlights the need for a multi-layered detection defense, combining upstream control, robust inline detection, and sophisticated analysis—underpinned by strong food safety culture and technology partnerships.