2025-12-29 – Weekly Food Processing News : Listeria hits persist in processing

Last week in the food processing community, members engaged in robust discussions around contamination control and efficiency improvements. A recurring theme was the persistent challenge of Listeria, with several threads dedicated to sharing experiences and solutions. Additionally, the community explored innovations in processing techniques, such as inline systems and powder induction, which could potentially enhance production efficiency and product quality.


This Week’s Hot Topics

Clean ATP, Listeria hits persist
Community members are sharing their strategies and frustrations with Listeria control. It’s a persistent issue, and this thread is packed with practical advice and new ideas.
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Powder induction for spice slurries — worth it
There’s a buzz around using powder induction systems for spice slurries. Participants are debating the cost-benefit balance and sharing their firsthand experiences.
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Training that links line changes to supply plans
This discussion highlights the importance of training programs that effectively integrate line changes with supply plans, aiming to reduce errors and enhance coordination.
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Dialing in metal detection without tanking throughput
Finding the sweet spot in metal detection is crucial. This thread focuses on optimizing detection settings without compromising on throughput.
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Inline NIR on gummy line — any wins
Members are exploring the use of inline NIR technology on gummy lines. Discussions revolve around accuracy and efficiency gains.
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My highest Listeria hit rate spot
A candid look into where Listeria is most likely to strike in processing environments, with members sharing their insights and mitigation tactics.
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ATP meter roasted my ‘clean’ pen
An amusing yet educational thread where an ATP meter revealed unexpected contamination, sparking a discussion on cleanliness standards.
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HPP for clean-label dairy — worth it
There’s a lively debate on using High Pressure Processing for creating clean-label dairy products, with opinions on both sides of the cost-effectiveness argument.
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Reducing false rejects on wet products
This thread dives into strategies for minimizing false rejects, particularly in the context of wet product inspections.
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Swapping batch mixing for inline shear
Members discuss the potential advantages of moving from batch mixing to inline shear systems, including consistency and efficiency improvements.
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Thanks for catching up with us. Stay informed, stay connected, and feel free to jump into these discussions. Your input is what makes our community thrive.

“Swapping batch mixing for inline shear” cut our post-mix Listeria swab hits once we added a 90-second 70°C caustic push between runs; caveat: watch shear heat — we had to drop rpm about 10% on mayo.

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What finally moved the needle for us was a 20‑minute 50°C dry‑air purge right after CIP on conveyors and slicer guards — “dry before you sanitize” — which cut our Zone 2 Listeria hits by about 70% and sped start‑up because there’s no condensate. Small caveat: mind belt materials; we cap at 55°C and spot‑check with a $40 IR gun to avoid softening.

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Our stubborn Listeria hits were coming from drains we kept splashing during CIP, . Switching to wet‑vac solids removal, capping drains during foam/rinse, and doing a weekly about 80°C steam + enzyme gel on each drain cut Zone 3 positives to near zero in two weeks; the fix was $300 in caps and a shop vac. Good drain-control notes here: Institute for Food Safety | CALS — anyone tried auto-closing drain valves during washdowns?

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We added a 15-minute ‘med-mix practice’ at bedside where parents use a $3 color-coded pill organizer to set up the first 24 hours of meds while we observe, then we swap in the actual discharge bottle to confirm dosing. It sticks better than handouts, but if postpartum fatigue is high we split it into two short run-throughs the next day; @MorganNP this pairs well with your rooming-in note, and March of Dimes has a simple visual card set: https://www.marchofdimes.org/find-support/topics/birth/going-home-nicu.

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Switched to sterile 0.01 µm point‑of‑use filters on compressed‑air blow‑offs and killed the aerosol problem on belts; about $200 per nozzle and zero drama to retrofit. @liamFrost99’s dryness point is right, and we add a 30‑minute pull with dehumidifiers to <45% RH post‑CIP so packaging doesn’t re‑wet. If budget’s tight, at least add a coalescing + activated‑carbon stage before the “inline” filter to keep oil and VOCs out.

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