What triggers an FDA Listeria recall in a dairy operation?

FDA initiates a recall when a manufacturer — or the agency through its own surveillance testing — identifies Listeria monocytogenes in a finished product or in an environmental sample with evidence of product contamination. Under FDA's recall classification system, Listeria in a ready-to-eat food like fresh cheese constitutes a Class I recall, meaning there is a reasonable probability that consuming the product will cause serious adverse health consequences or death. Manufacturers can also initiate voluntary recalls when their own testing or a customer complaint reveals the issue.

How often should a fresh cheese manufacturer test for Listeria?

There is no single FDA-mandated testing frequency, but FDA's guidance and the requirements at 21 CFR § 117.165(b)(2) require that environmental monitoring be risk-based and sufficient to verify that sanitation preventive controls are operating effectively. For a ready-to-eat fresh cheese operation, most food safety practitioners recommend monthly or bi-monthly environmental sampling at minimum, with additional testing triggered by any positive finding. Finished product testing alone is not an adequate substitute for environmental monitoring — by the time Listeria shows up in a finished product test, contamination has almost certainly been present in the environment for some time.

Does FSMA's Preventive Controls rule apply to small artisan cheese makers?

Yes, with nuances. Very small businesses under $1 million in total annual sales of human food may qualify for modified requirements under 21 CFR § 117.5, but the Current Good Manufacturing Practice (CGMP) requirements at Subpart B of 21 CFR Part 117 apply to all food manufacturers under FDA jurisdiction regardless of size. The CGMP requirements include the sanitation and personnel hygiene practices most relevant to Listeria control. Modified requirements on recordkeeping and food safety plan specifics do not eliminate the core obligation to prevent Listeria contamination in ready-to-eat products.

What is the difference between testing for Listeria species and Listeria monocytogenes?

Listeria species (Listeria spp.) testing looks for the broader genus, which includes monocytogenes alongside several non-pathogenic species. It is more sensitive as an early indicator of environmental contamination and is less expensive than species-specific testing, which is why most EMPs use it for routine swabbing. Listeria monocytogenes testing is species-specific and is deployed when a Listeria spp. positive requires investigation, or for confirming product safety. A well-designed EMP treats a Listeria spp. positive as a signal to investigate and sanitize, and a Listeria monocytogenes positive as a signal to consider product holds and potential recall evaluation.

What corrective actions are required when a dairy manufacturer finds Listeria in environmental monitoring?

Under 21 CFR § 117.150, corrective actions must be taken when a preventive control — including sanitation controls verified by environmental monitoring — is found to be inadequate. A Listeria spp. positive should trigger expanded sampling to map the contamination, targeted sanitation intervention at the positive site and surrounding area, a review of any product that may have been exposed during the contamination window, and a root-cause investigation documented in writing. If the finding is Listeria monocytogenes rather than Listeria spp., or if Zone 1 (direct food-contact surfaces) are implicated, manufacturers should also evaluate whether voluntary product holds or recall are warranted based on the risk to consumers.

Listeria Prevention Controls Every Dairy Manufacturer Needs

When the FDA posts a recall notice, most readers see a company name and a product. I see a gap in a quality system — usually a specific, identifiable gap that a functioning food safety program would have caught before product ever left the facility.

The June 2026 recall of Requeson Cheese by Nelson & Isa Lacteos LLC of Bayshore, NY, for possible Listeria monocytogenes contamination is exactly that kind of case. The FDA's recall notice identifies the product as 1lb packages of fresh Requeson — a ready-to-eat cheese that undergoes no kill step after manufacturing. If Listeria enters the production environment and the operation lacks the controls to find it and eliminate it, contaminated product reaches consumers. That is what happened here.

This article is not about that company. It is about the system — or the absence of one — that allows Listeria to reach finished product in the first place, and what any dairy manufacturer can do to make sure they are not the next name on an FDA recall notice.

Why Listeria Is Uniquely Dangerous for Dairy Operations

Listeria monocytogenes causes an estimated 1,600 illnesses and 260 deaths in the United States every year, according to CDC surveillance data. It kills roughly one in five people it infects — one of the highest case-fatality rates of any foodborne pathogen. The populations at greatest risk are young children, elderly individuals, pregnant women, and people with compromised immune systems — exactly the populations most likely to consume fresh cheeses like Requeson.

What makes Listeria particularly hard to manage in dairy environments is its biology. It thrives in cold, wet conditions, which is exactly what a cheese plant provides. It forms biofilms on equipment surfaces that resist standard sanitation. It persists for months or years in floor drains, cooler door gaskets, condensate lines, and the crevices of aging equipment. A single undetected harborage site can contaminate product run after run until someone looks for it.

Listeria monocytogenes is the leading pathogen of concern for fresh, ready-to-eat cheese manufacturers under FDA jurisdiction, and its presence in a finished product is almost always a sign that the facility's environmental controls were either absent or not functioning as designed.

The FDA's position on Listeria in ready-to-eat foods has not softened. Under 21 CFR § 117.130(c), Listeria monocytogenes is a known or reasonably foreseeable hazard for any ready-to-eat food manufactured in a facility where the pathogen could be introduced. That means if you make fresh cheese, you are legally required to have a plan for it — no exceptions for small operations, no carve-outs for artisan producers.

The Regulatory Framework: FSMA and 21 CFR Part 117

The Food Safety Modernization Act, signed into law on January 4, 2011, shifted FDA's food safety framework from reaction to prevention. The implementing regulation — the Preventive Controls for Human Food rule, codified at 21 CFR Part 117 — requires food manufacturers to maintain a documented food safety plan that includes:

A written hazard analysis (§ 117.130)
Preventive controls adequate to control identified hazards (§ 117.135)
Monitoring procedures for those controls (§ 117.145)
Corrective action procedures (§ 117.150)
Verification activities, including product and environmental testing (§ 117.165)
A supply-chain program where incoming materials could introduce hazards (§§ 117.410–117.475)

For Listeria specifically, § 117.135(c)(3) requires sanitation controls that address "microbiological contamination of food, food-contact surfaces, and food-packaging materials." An environmental monitoring program — the most powerful tool a dairy manufacturer has against Listeria — falls under the verification requirements at § 117.165(b)(2), which expressly requires environmental monitoring where Listeria is a hazard identified in the facility's food safety plan.

FSMA's compliance deadlines for operations under $1 million in annual sales offered more flexibility on timing, and very small businesses may qualify for modified requirements under § 117.5. But the underlying obligation to control Listeria exists for every food manufacturer under FDA jurisdiction, including small artisan cheese makers. The size of your operation affects your paperwork obligations, not your liability when a consumer gets sick.

What an Environmental Monitoring Program Actually Looks Like

An environmental monitoring program (EMP) is the closest thing the dairy industry has to a Listeria early-warning system. The concept is straightforward: you test surfaces throughout your facility on a rotating schedule, looking for Listeria or its indicator organism, so you can find contamination in your environment before it reaches your product.

Industry data consistently shows that dairy processing facilities without an active EMP are three to four times more likely to experience a Listeria-related recall event than facilities running a robust program — and that an EMP detecting Listeria in Zones 3 or 4 gives manufacturers the window to intervene before Zone 1 food-contact surfaces are implicated.

A well-designed EMP for a fresh cheese operation should include:

Zone-based sampling. The food safety community uses a four-zone model. Zone 1 covers direct food-contact surfaces. Zone 2 covers areas near food-contact surfaces, like equipment frames and conveyor supports. Zone 3 covers general processing areas — floors, drains, walls. Zone 4 covers non-processing areas such as break rooms and traffic paths. A good EMP starts with aggressive sampling in Zones 3 and 4, where Listeria tends to harbor, and then traces contamination inward toward Zone 1 when findings occur.

Indicator organism first. Testing for Listeria species (Listeria spp.) rather than immediately testing for monocytogenes is more sensitive and less expensive. If you find Listeria spp., you investigate and sanitize. If you find L. monocytogenes, you have a more serious problem that likely requires a product hold and expanded corrective action.

Rotating, risk-based sample sites. An EMP that tests the same ten sites every month will find the same thing every month. Effective programs include both fixed sites and rotating sites, with additional sampling triggered by any positive finding. The goal is to keep Listeria guessing, not to confirm a location you already know about.

Corrective action triggers with documentation. Every positive environmental finding should trigger an immediate investigation: What was the source? Where else might contamination have spread? Was product at risk? FDA inspectors reviewing EMP records will look at whether positive findings led to documented corrective actions. An EMP that finds Listeria and doesn't do anything about it is almost worse than no EMP at all — it demonstrates the manufacturer knew and chose not to act.

Sanitation Controls That Actually Address Listeria

Most food manufacturers have sanitation programs. Fewer have sanitation programs designed specifically to address Listeria harborage. The difference matters more than most small operations realize.

Listeria doesn't hide where cleaning is easy. It hides in floor drain debris, in the threads of bolts, in the seams of equipment designed for function rather than cleanability, in corners where walls meet floors, in condensate that drips from overhead pipes onto food-contact surfaces. A sanitation program that passes a visual inspection on Monday can still have active Listeria harborage sites producing product contamination by Friday.

Effective Listeria-focused sanitation in a fresh cheese operation means:

Drain cleaning on a documented schedule, with physical removal of organic material followed by sanitizer contact — not just a sanitizer flush
Equipment disassembly for deep cleaning at defined intervals, covering all surfaces that routine clean-in-place cycles don't reach
Condensate control — documented inspection and management of overhead moisture sources, which are a classic Listeria vector in dairy environments
Hygienic zoning — physical separation between raw and ready-to-eat production areas, with traffic controls and footwear protocols that prevent cross-zone contamination
Pre-operational verification — physical inspection and ATP or microbiological testing before production starts, not after a full day of running

Under 21 CFR § 117.135(c)(3), these are not best practices. They are required preventive controls when Listeria has been identified as a hazard — which it must be for any RTE dairy product.

The Comparison Every Dairy Manufacturer Should See

Control Element	Adequate Program	Gap That Creates Recall Risk
Environmental Monitoring	Zone-based, rotating sites, triggered follow-up on positives	No EMP or fixed-sites-only testing
Sanitation Design	Listeria-targeted, documented disassembly intervals, condensate controls	Visual-pass standard, no targeted protocol
Hygienic Zoning	Physical barriers, traffic controls, footwear protocols	Open-floor layout, no zone separation
Corrective Action	Documented investigation, product hold criteria, root cause	No written procedure for environmental positives
PCQI Oversight	Trained PCQI reviews and approves food safety plan	No qualified individual identified
Finished Product Testing	Used as supplementary verification, not primary control	Sole testing approach, no environmental monitoring
Supplier Controls	Incoming milk/ingredients from verified, approved sources	No formal supplier verification program

A Listeria recall at a small cheese operation almost always reflects multiple gaps in the right column, not a single isolated failure. Each gap alone is manageable. Several together is what produces the pattern: Listeria establishes itself in the environment, no system detects it, product ships.

The PCQI Requirement — And Why Small Operations Can't Skip It

FSMA's Preventive Controls rule requires that the food safety plan for any facility subject to 21 CFR Part 117 be prepared by, or under the oversight of, a Preventive Controls Qualified Individual (PCQI). A PCQI is someone who has completed the standardized curriculum developed by the Food Safety Preventive Controls Alliance (FSPCA) in collaboration with FDA, or who has equivalent training and experience.

This requirement does not exempt small manufacturers. In my experience working with small dairy operations over the past eight-plus years, the absence of a PCQI — or a nominal PCQI who completed training years ago and hasn't reviewed the facility's food safety plan since — is one of the most common gaps I encounter, and it tends to be the root cause of every other gap on the list. If no one in the facility has the training to write a proper hazard analysis, the hazard analysis won't capture Listeria correctly. If the hazard analysis misses Listeria, the sanitation controls won't be written to address it. The whole system builds on that foundation, and a weak foundation produces weak controls.

The FSPCA training is available through a network of trainers across the country and online. The investment is modest relative to the cost of a Class I recall, which typically runs into the hundreds of thousands of dollars when you factor in product destruction, consumer notification, investigation, corrective action, and the reputational fallout that follows.

Practical Steps for Dairy Manufacturers Right Now

If you're a fresh cheese manufacturer reading this in the wake of the Nelson & Isa Lacteos recall, here is what I'd suggest looking at first:

Pull your food safety plan. Does it identify Listeria monocytogenes as a hazard requiring a preventive control for your RTE products? If it does not, that is where you start.
Review your environmental monitoring records. Are you testing for Listeria species in your processing environment? When did you last get a positive finding, and what happened next? If you have never had a positive finding after months of testing, either your facility is genuinely clean or your sampling isn't reaching the right sites.
Walk your sanitation SOPs against your actual facility. Floor drains, equipment seams, overhead moisture sources — do your written procedures address these specifically, and do your sanitation records reflect that they're being done?
Confirm your PCQI status. Who in your organization completed FSPCA training? When? Does your current food safety plan reflect their ongoing oversight?

FDA's inspection frequency for small food manufacturers under FSMA has increased as the agency has moved into the maintenance phase of FSMA implementation. Inspectors are trained to ask for food safety plans, check EMP records, and verify that positive environmental findings were followed by documented corrective actions. Finding your gaps before an inspector does is the whole point of having a quality system.

A Listeria recall in a dairy operation is almost never random contamination. It is almost always a predictable outcome of specific control failures — failures that an adequate food safety program, built on 21 CFR Part 117 requirements and maintained by a trained PCQI, would have identified and corrected before any product shipped.

How Certify Consulting Can Help

At Certify Consulting, we work with food manufacturers — including small dairy and specialty cheese operations — to build and validate food safety plans that hold up under FDA scrutiny. That includes EMP design and review, hazard analysis development, sanitation program gap assessments, PCQI training coordination, and pre-inspection readiness evaluations. Across 200+ clients over eight-plus years of practice, we've maintained a 100% first-time audit pass rate.

If you are not confident that your current program would survive an FDA inspection, that is a conversation worth having now — well before a recall forces it. Learn more about our FSMA Preventive Controls compliance services or reach out directly to discuss your specific situation.

Last updated: 2026-06-17