US import compliance
Low-acid and acidified foods: the filings that decide whether a can clears
The product’s formulation, finished equilibrium pH, water activity, process and storage conditions determine the applicable FDA requirements. A pH result alone does not establish the regulatory classification.
Last reviewed: September 22, 2026
01
Where the line falls
FDA classification depends on the product’s formulation, finished equilibrium pH, water activity, process, storage conditions and any applicable product-specific exclusions—not simply the product name or container.
| Category | Finished equilibrium pH | Water activity |
|---|---|---|
| Low-acid canned food | above 4.6 | above 0.85 |
| Acidified food | 4.6 or below | above 0.85 |
An acidified food is a low-acid food to which acid or an acid food is added so that the finished equilibrium pH is 4.6 or below and water activity remains above 0.85. A naturally acid food is not an acidified food merely because its pH is below 4.6. Product-specific exclusions also matter: tomatoes and tomato products with a finished equilibrium pH below 4.7 are not classed as low-acid foods, and foods preserved by controlled fermentation may require separate evaluation.
Equilibrium pH, not the pH of the brine. The measurement that matters is the finished product at equilibrium, solid and liquid phases settled together. A brine testing below 4.6 on the filling line proves nothing if the drained fruit has not equilibrated to it.
02
A worked example: two olives
Olives make the point better than any diagram, because the same crop splits across both regimes depending on how it is processed.
| Preparation | Typical finished pH | US classification |
|---|---|---|
| Black olives, ripe-processed | 6.0 - 7.5 | Low-acid canned food - requires a full thermal scheduled process |
| Green olives acidified by adding acid | 4.6 or below, with water activity above 0.85 | Acidified food where the regulatory definition applies; confirm the product and process |
| Olives fermented under controlled conditions | Confirm finished equilibrium pH | Not automatically an acidified food; evaluate fermentation, subsequent additions and the applicable exclusions |
The same crop can follow different regulatory paths. Confirm classification with the processor and process authority for the actual recipe, process and container. Do not assume one filing covers every olive preparation or pack size.
03
What the producing site must file
These obligations sit on the processor, including processors outside the United States who export there. They are separate from, and additional to, food facility registration.
| Step | What it is | When |
|---|---|---|
| FCE | Food Canning Establishment registration, on Form FDA 2541. Produces the establishment FCE number. | Not later than 10 days after first processing or packing such foods. |
| Process filing | The scheduled process for each product in each container size. Form FDA 2541e for acidified foods; Forms FDA 2541d, 2541f or 2541g for low-acid canned foods. | Before packing a new product, and no later than 60 days after registration. |
| SID | Submission Identifier - the date the filing form was created plus a sequence number, identifying that specific filing. | Issued with each process filing. |
Cited at 21 CFR 108.25(c)(1), 108.35(c)(1) and 108.35(c)(2).
An FCE number is not a pass. It says the establishment is registered. It says nothing about whether your product, in your container size, has a filed scheduled process. That is what the SID covers, and it is product-and-format specific. Ask for both.
04
What a buyer should check
- Which requirements apply to this exact product? Ask for the formulation, finished equilibrium pH, water activity, process, storage conditions and any applicable exclusions—not a category name alone.
- FCE number for the producing site, and confirmation it is current.
- SID covering the exact product and container size. A change from a 400 g jar to a #10 / A10 can is a different filing.
- Does the filing match the recipe actually shipped? A reformulation can change the classification or scheduled process. Reconfirm the actual recipe, equilibrium pH, water activity, process and container rather than assuming the previous filing still applies.
- Remember the FSVP overlap. For microbiological hazards controlled under 21 CFR Part 113, the importer verifies and documents compliance with Part 113; every other hazard remains subject to FSVP.
05
How we handle it
- Formulation, finished equilibrium pH, water activity, process, storage and applicable exclusions reviewed for each canned line before the U.S. classification is stated
- FCE and the process filing reference held per producing site, per product, per container format
- Format changes treated as a new filing question, not a packaging decision
- Filing status issued with the shipment document set
Product programs this guide applies to
Next step
Planning a program that has to meet these requirements?
Send the product, target market, pack format and expected volume. We review the commercial fit and come back with the questions that matter before a quotation.
Source and scope
Source. 21 CFR Parts 108, 113 and 114, and the FDA published guidance on establishment registration and process filing for acidified and low-acid canned foods. Provisions are cited inline. FDA: acidified and low-acid canned foods.
Scope. pH ranges shown for olives are indicative of typical preparations and are given to illustrate the classification test - they are not a specification. Classification for any given product requires its own formulation, finished equilibrium pH, water activity, process and storage conditions, including any applicable exclusions. General information for commercial importers, not legal advice; confirm current requirements with the FDA, your process authority and your customs broker.
Inquiries: sales@alphatradecorp.com