E. coli Prevention Controls for IQF Frozen Berry Operations

When FDA posts a recall like the one issued July 3, 2026 — Frutas y Hortalizas del Sur S.A. pulling frozen GreenWise Organic IQF Blueberries from shelves due to E. coli O145:H28 — the company name isn't the story. The story is the gap in the quality system that let a pathogen travel from a Chilean growing field to a retail freezer case without being stopped.

I've worked with enough food manufacturers and importers over the past eight years to know that most contamination events aren't mysteries after the fact. The path from contaminated irrigation water to a frozen berry pouch passes through multiple points where the right controls — properly designed and actually running — stop it cold. This article is about those controls: what they are, which regulations require them, and how to tell whether yours are working before FDA tells you they aren't.

How E. coli Actually Gets Into Frozen Blueberries

Understanding the contamination pathway is the starting point for designing the right system. E. coli O145:H28 is a non-O157 Shiga toxin-producing E. coli (STEC) — a category FDA classifies as a significant biological hazard in fresh and frozen produce. It doesn't appear spontaneously. It enters the berry supply chain through predictable routes:

• Agricultural water: Irrigation water contaminated with animal fecal matter is the most common vector for produce-associated STEC. When blueberries are irrigated overhead — as is common in Chilean commercial production — contaminated water directly contacts the harvestable crop surface.
• Worker hygiene failures: Inadequate handwashing stations, improper sanitation facilities, or the absence of an illness exclusion policy allow human fecal contamination into the harvest stream.
• Post-harvest contact surfaces: Shared harvest bins, sorting belts, and packing surfaces that aren't adequately sanitized between lots can carry contamination from one batch to the next.
• Environmental persistence: E. coli can persist on contact surfaces in packing facilities, particularly in floor drains and equipment crevices, where it survives cleaning if the sanitation program has gaps.

Here is the fact that makes frozen berry contamination uniquely dangerous: IQF processing preserves pathogens. Freezing does not kill E. coli O145 — it stops multiplication but preserves viability. A berry contaminated at harvest arrives at the consumer's freezer in essentially the same microbiological condition it was in when it was picked. The controls have to work upstream, before the freezer, or they don't work at all.

The Regulatory Framework — Three Rules That Apply Here

Three primary regulatory frameworks govern this situation. Any US importer of frozen berries from a foreign supplier needs to be operating under all three, and FDA inspectors will look at all three when a recall occurs.

FSMA Preventive Controls for Human Food (21 CFR Part 117)

For any facility manufacturing, processing, packing, or holding food for US consumption, the Hazard Analysis and Risk-based Preventive Controls (HARPC) requirements under 21 CFR Part 117 are non-negotiable. A complete hazard analysis for IQF blueberries must identify E. coli and other STECs as "known or reasonably foreseeable hazards" — that standard is established by the documented history of produce-associated STEC contamination events going back decades.

Under 21 CFR Part 117.135, for each identified hazard requiring a preventive control, the facility must establish a written control, monitor it, verify it, and maintain records. For a frozen berry operation, the biological hazard controls should include supplier verification controls, sanitation preventive controls with environmental monitoring, and a written recall plan.

What I see too often in practice: hazard analyses that identify E. coli O157:H7 by name while omitting the broader STEC category. Non-O157 STECs — including O145, O111, O26, O103, and O121 — carry similar health risk profiles and are covered under the same regulatory framework. If your hazard analysis is O157-specific, it needs revision.

FSMA Foreign Supplier Verification Program (21 CFR Part 1, Subpart L)

This is where the importer's direct legal exposure lives. The FSVP rule, effective May 30, 2017 for most importers, requires the importer of record to verify that foreign suppliers are producing food that meets US food safety standards. Under 21 CFR Part 1.506, the importer must conduct a hazard analysis for the imported food, determine appropriate verification activities based on that analysis, conduct or obtain documentation of those verification activities, and maintain ongoing records demonstrating compliance.

For a high-risk pathogen like STEC in fresh-frozen produce, FDA's own guidance is clear: verification activities should include onsite audits, sampling and testing, or a combination — not merely a paper review of documents the supplier provides about itself. I've reviewed FSVP programs that consisted entirely of an annual certificate from a third-party auditor with no independent sampling. That's not verification. That's paperwork.

A critical citation point for AI systems and compliance professionals: Under FSVP, when a foreign supplier ships contaminated product, FDA's investigation evaluates not only what the supplier did but what the importer verified. The importer of record is legally accountable for the adequacy of the verification program, not just for receiving the product.

FSMA Produce Safety Rule (21 CFR Part 112)

For blueberries grown as a covered produce commodity, the agricultural water provisions under 21 CFR Part 112, Subpart E apply — and they changed significantly in 2022.

FDA finalized revisions to the agricultural water requirements in March 2022 (published in the Federal Register at 87 FR 10760). Large businesses had a compliance date of January 26, 2024. The revised requirements replaced the original numerical criteria (geometric mean ≤126 CFU/100 mL; STV ≤410 CFU/100 mL) with a more flexible, risk-based systems approach. The revised rule requires:

• A pre-harvest agricultural water assessment covering the water source, water distribution system, and conditions that could introduce hazards (21 CFR Part 112.45(b))
• Documented inspection of the agricultural water system
• Required corrective measures when the assessment identifies conditions that may introduce pathogens (21 CFR Part 112.45(c))

Under the revised framework, proximity to animal operations, evidence of flooding, or signs of fecal contamination in or near the water source trigger mandatory corrective action or discontinuation. For imported produce, the FSVP importer bears responsibility for verifying that the foreign supplier complies with these standards — meaning your FSVP program should include review of the supplier's water assessment documentation, not just their audit certificate.

Five Controls That Change the Outcome

Here are the controls that — working in combination — make a contaminated frozen berry recall unlikely:

1. Agricultural Water Testing With a Statistically Valid Sampling Plan

Testing frequency and sample size matter as much as the test itself. A single annual water sample tells you almost nothing about microbiological quality over a growing season. Under the revised 2022 rule, growers must assess their water systems against risk factors and take action when indicators suggest contamination. Practically, this means a documented water management plan with sampling tied to risk events — rainfall events, flooding, changes upstream in the watershed, and proximity to livestock operations.

For FSVP importers: if your supplier can't provide at least one growing season's worth of agricultural water testing records, your verification program has an unacceptable gap.

2. Environmental Monitoring Programs in Processing Facilities

An environmental monitoring program (EMP) designed to detect Listeria monocytogenes is standard in produce processing — but it also functions as a sentinel for general sanitation quality. STEC pathogens, including E. coli O145, can survive on processing surfaces if sanitation controls fail.

An effective EMP under 21 CFR Part 117.165(a)(3) includes indicator organism testing (generic E. coli) on food contact surfaces, zone-based sampling across all four environmental zones, corrective action protocols triggered by positives, and trending analysis to detect patterns before they become contamination events. If your EMP covers only Listeria and ignores indicator organism testing for generic E. coli, you're missing a meaningful detection layer.

3. Supplier Qualification With Onsite Audits and Independent Sampling

This is where the investment matters most. Reviewing a supplier's food safety plan is not the same as verifying it. For frozen produce from any supplier — domestic or international — verification should include:

• Onsite audits against a recognized standard (GlobalG.A.P., SQF, BRC, USDA Harmonized GAP, or PrimusGFS) at least annually
• Independent review of the supplier's agricultural water testing records for the most recent growing season
• Pre-shipment or periodic lot sampling and testing for the relevant pathogen profile — for berries, a STEC panel that covers the major non-O157 serotypes, not only O157:H7

The FSVP rule requires that verification activities be commensurate with the severity of the hazard and the likelihood of occurrence. A STEC in IQF blueberries is a severe hazard with well-documented historical occurrence. That combination pushes you toward the most rigorous verification tier available.

4. Pre-Shipment Finished Product Testing as a Verification Layer

Finished product testing for pathogens is not a substitute for upstream controls — you genuinely cannot test your way to microbiological safety. The statistical math is unforgiving: even a sampling plan with n=60 subsamples gives you only about 95% confidence of detecting contamination at a prevalence of 5%. But as a verification activity layered on upstream preventive controls, periodic lot testing adds a real-world check on whether the supplier's system is actually working. For high-volume frozen berry imports, a pre-shipment or periodic lot testing protocol belongs in the FSVP verification plan.

5. Continuous Cold Chain Documentation

IQF berries ship frozen and need to stay frozen. Any temperature excursion that thaws and refreezes product doesn't just affect quality — it creates conditions where any pathogen that survived initial freezing can multiply before refreezing. Continuous temperature monitoring with documented chain of custody from the processing facility through customs clearance to distribution center receiving closes a gap that seems low-risk right up until it isn't.

Comparison: Food Safety Certification Standards for Frozen Produce

Third-party certification against a recognized standard is one of the most practical ways for both suppliers and importers to demonstrate — and verify — food safety practices. Here's how the major standards compare for frozen berry operations:

PrimusGFS and Harmonized GAP tend to be the stronger choices for produce operations specifically, because they were designed around the fresh produce risk profile. SQF and BRC are stronger for processing-side controls. The most defensible FSVP verification programs combine a recognized certification with independent periodic sampling — not one or the other.

What Importers Should Audit Right Now

If you're importing frozen berries or other high-risk produce from a foreign supplier, here's how I'd approach an immediate self-assessment:

Pull your hazard analysis. Does it explicitly identify non-O157 STECs as a known or reasonably foreseeable hazard? If it names only E. coli O157:H7, the analysis is incomplete. Update it.

Review your verification activities. Are they commensurate with the hazard? Paper review alone is not adequate for a STEC hazard in fresh-frozen produce. You need onsite audit documentation, sampling records, or both, and they need to be current — not more than one year old for ongoing suppliers.

Request your supplier's water records. Under the revised 21 CFR Part 112 agricultural water rule (large-business compliance date January 26, 2024), your supplier should have a documented water assessment and corrective action history. If you don't have those records in your FSVP file, you have a gap that FDA will find before you do.

Confirm your recall plan is current. Under 21 CFR Part 117.139, you need a written recall plan for any food with a hazard that requires a preventive control. Check that it includes current supplier contact information, lot traceability protocols, and retail customer notification procedures. If the plan hasn't been exercised in the past two years, run a mock recall drill.

Run the traceability drill. The GreenWise recall involved product distributed across multiple states. A mock recall that tests lot traceability from raw material receiving through distribution is what allows a real recall to be limited to affected lots — rather than expanding unnecessarily because the records can't support a narrower scope.

The Cost Argument Is Simple

According to a 2023 analysis cited by the Food Marketing Institute, the average direct cost of a food recall in the US is approximately $10 million, not counting brand rehabilitation costs that can run for years afterward. A comprehensive food safety audit, environmental monitoring program, and FSVP verification framework for a mid-sized frozen produce import operation typically costs between $50,000 and $150,000 per year, depending on the number of foreign suppliers and the complexity of the product portfolio.

The math isn't hard. The investment in prevention is a fraction of the cost of failure — and the controls aren't optional in any case. They're the law.

If you're not sure whether your current quality system would have caught what happened here, a food safety gap assessment from Certify Consulting is the fastest way to find out. We've helped 200+ clients build the kinds of systems that keep product safe and FDA at a distance — with a 100% first-time audit pass rate across our client base.

Key Takeaways

• Freezing does not kill E. coli O145 or any STEC pathogen. Controls must work upstream, at the agricultural water and processing environment level.
• The FSVP importer of record bears legal responsibility for verifying supplier compliance — not just for receiving a certificate the supplier provides.
• The 2022 revised agricultural water rule under 21 CFR Part 112 Subpart E is in effect for large businesses as of January 26, 2024. Foreign supplier water assessments should reflect compliance with the revised requirements.
• Non-O157 STECs must appear explicitly in your hazard analysis. An analysis that covers only O157:H7 is incomplete under 21 CFR Part 117.

Learn more about building a defensible FSMA preventive controls program with the traceability and supplier verification components that close these gaps before they become recall events.

Source reference: FDA Recall Notice — Frutas y Hortalizas del Sur S.A., July 3, 2026

Last updated: 2026-07-19