Who this is for
This guide is for food startups, co-packers, shelf-stable sauce brands, jarred product businesses, bakeries with fillings, refrigerated RTE food makers, private label brands, and QA coordinators asked for process support.
It is especially useful when a buyer, health department, co-packer, auditor, or regulator asks for a scheduled process, process authority letter, pH support, water activity data, thermal process support, or product safety review.
What is a process authority?
A process authority is a qualified expert who has the technical knowledge needed to evaluate a food product and process. For acidified and low-acid canned foods, the process authority concept is tied to technical evaluation of processing, acidification, thermal process, and critical factors.
For other products, a qualified food safety expert may be asked to review shelf-life, formulation, pH, water activity, storage conditions, kill step validation, post-lethality exposure, or other safety controls.
What is a process authority letter?
A process authority letter is written support that describes the product and the reviewed process. Depending on the product, it may identify the scheduled process, critical factors, pH target or limit, water activity, processing conditions, storage requirements, or other controls.
The letter should match the actual product version. If the formula, container, fill weight, process, or storage condition changes, the business should review whether the letter still applies.
Use this page with Acidified Foods FDA Requirements, Low-Acid Canned Foods Requirements, Food Safety Plan Template, and the templates hub.
Products that often trigger process authority review
Process authority review may be commonly requested when product safety depends on pH, water activity, heat treatment, packaging, refrigerated storage, reduced oxygen packaging, or shelf-stable distribution.
The request may come from a regulator, co-packer, customer, retailer, certification auditor, insurance review, or internal QA team.
Acidified foods
Acidified foods often require process authority support because acidification is part of the safety control. The process authority may review formulation, equilibrium pH, acid source, process steps, container size, and critical factors.
Low-acid canned foods
Low-acid canned foods require careful thermal process review because the product is shelf-stable in a hermetically sealed container. Process authority support may include scheduled process development and critical factor review.
Refrigerated RTE foods
Refrigerated ready-to-eat products may trigger review when shelf-life, pathogen control, post-lethality exposure, packaging, or storage temperature is part of the safety strategy. A process authority letter does not remove the need for an appropriate food safety plan.
Shelf-stable sauces
Shelf-stable sauces may need review when pH, water activity, heat treatment, preservatives, hot fill, container closure, or product distribution conditions are used as controls.
Bakery fillings or high-moisture products
Bakery fillings, icings, custards, cream fillings, and other high-moisture components may need technical review when water activity, pH, refrigeration, or shelf-life claims affect safety and quality.
What information a process authority may request
A process authority may request:
- Full formula with percentages or weights.
- Ingredient specifications.
- pH and water activity data.
- Processing flow and equipment.
- Time and temperature records.
- Container size and closure information.
- Storage and distribution conditions.
- Shelf-life target.
- Lab results or challenge study information where applicable.
- Intended consumer and use.
- Label draft and claims.
What the letter may include
The letter may include product identity, formula version, critical factors, pH or water activity limits, process parameters, container information, storage conditions, instructions for monitoring, and conditions under which the recommendation applies.
For acidified or low-acid canned foods, it may support scheduled process and filing work. The exact content depends on the product and the process authority’s scope.
What the letter does not replace
A process authority letter does not replace FDA registration where required, process filing where required, local permits, food safety plans, HACCP plans, preventive control records, label compliance review, employee training, sanitation controls, or customer requirements.
It also does not protect a business from formula drift. The production team still needs to make the product exactly as reviewed.
What to include
Before requesting review, prepare:
- Product description and intended use.
- Formula and formula version.
- Ingredient specifications.
- Process flow diagram.
- Packaging and container details.
- Target shelf-life and storage condition.
- Lab data, pH, water activity, and process records.
- Label draft and claims.
- Intended production facility.
- Questions that need a written answer.
Records to keep
Keep process authority correspondence, final letter, formula version, supporting data, lab results, pH and water activity records, scheduled process documents, process filing confirmations where applicable, label version, change control records, and production records tied to lot codes.
Common audit/customer/regulatory request
Common requests include a process authority letter, scheduled process, pH records, water activity records, process filing evidence, process deviation records, shelf-life support, and proof that production records match the reviewed process.
Buyers may also ask whether the process authority reviewed the exact commercial formula and packaging, not only a prototype.
Practical checklist
- Confirm product category and intended shelf condition.
- Gather formula, ingredient, and packaging details.
- Collect pH and water activity data using appropriate methods.
- Document the process flow and critical steps.
- Identify any heat treatment, acidification, or preservative controls.
- Ask whether FDA process filing or state review may apply.
- Keep the final letter with controlled formula records.
- Review the letter after formula, packaging, equipment, or shelf-life changes.
Common mistakes
Common mistakes include sending an incomplete formula, changing the recipe after review, using the letter for a different container, assuming a letter is the same as regulatory approval, and not training production employees on the reviewed process.
Another mistake is treating the letter like a sales document. It belongs in the food safety and document control system.
QA perspective
From a QA perspective, the process authority letter should be tied to formula control, product launch approval, label review, customer documentation, and change control. If the production batch does not match the reviewed formula and process, the letter may not support that lot.
The practical goal is traceability from product version to process support to production record to finished lot.
Source notes
Verify process authority and scheduled process topics with official sources:
- FDA Guide to Inspections of Low Acid Canned Food: Processing Authorities.
- FDA Acidified & Low-Acid Canned Foods Guidance Documents & Regulatory Information.
- FDA Guide to Inspections of Low Acid Canned Food: Process Filing Requirements.
- eCFR 21 CFR Part 113 and 21 CFR Part 114.
Official requirements should be verified with FDA, state/local regulators, process authorities, customers, certifying bodies, or qualified professionals.
FAQ
Is a process authority letter the same as FDA approval?
No. A process authority letter is not FDA approval. It is technical support from a qualified expert and should be used with applicable FDA, state, customer, and certification requirements.
Who can be a process authority?
A process authority should have appropriate expert knowledge for the product and process being reviewed. The needed expertise can differ for low-acid canned foods, acidified foods, refrigerated RTE foods, and other products.
When should I contact a process authority?
Contact a process authority before commercial launch, before changing the formula or package, and before promising shelf-stable or refrigerated safety controls to a buyer or co-packer.