Manufacturing
Changeover and allergen sequencing records behind co-packer scheduling
By SourceX Editorial · Updated
Short answer
Allergen changeover records are the run logs, sanitation records and verification results that show how long each product-to-product switch really took and what cleaning it required. Organized into a changeover matrix of from-SKU, to-SKU, allergen class, clean type and actual minutes, they let a co-packer schedule from evidence instead of one planner's memory.
Key takeaways
- A changeover matrix records, for each pair of products, the allergen classes involved, the clean type required and the time it actually took.
- Actual times come from run logs and sanitation records, not from the planned times in the schedule.
- Measure each changeover from the last good unit of one product to the first good unit of the next.
- Brand formulas and specifications belong to the brand; changeover times and sanitation records are usually the co-packer's own operating records.
- AI scheduling tools need the same matrix, so building it pays off with or without new software.
Which records describe a changeover?#
A changeover at a co-packer is described by at least five records that are rarely kept together: the production run log, the sanitation record, the allergen verification result, the pre-operational inspection and the label or packaging verification. Each one is created by a different team, often on a different form.
Scheduling usually runs on none of them. In many plants the sequence lives in the head of one experienced planner who knows which products can follow which, how long a wet wash on line two really takes, and which brand insists on a full clean even when the allergen profile would not require it.
- Run logs: line, SKU, lot, start and stop times, and downtime codes.
- Sanitation records: clean type performed, crew, start and finish, chemicals and sign-off.
- Allergen verification: visual inspection results and any allergen-specific test results.
- Pre-operational inspection: release of the line before the next product starts.
- Label and packaging verification: confirming the right label and allergen statement for the next run.
- Holds and deviations: product held, reworked or rejected after a changeover issue.
The fields in a changeover matrix#
A changeover matrix is a table with one row for every ordered pair of products a line runs, holding the clean type that pair requires and the time it actually takes. Order matters: switching from a product without an allergen to one with it usually needs less cleaning than the reverse.
Build the matrix at the level the plant schedules. If many SKUs share a formula and allergen profile and differ only in pack size, group them into a product family so the matrix stays small enough to use.
| Field | Source record | Notes |
|---|---|---|
| Line | Run log | Matrices differ by line because equipment differs |
| From SKU or family | Run log | The product ending its run |
| To SKU or family | Run log | The product starting next |
| Allergen class of each | Formula or specification | Use the plant's allergen matrix, not free text |
| Clean type required | Allergen control program | For example dry clean, wet wash or full allergen clean |
| Planned minutes | Production schedule | What the planner assumed |
| Actual minutes | Run log and sanitation record | Last good unit to first good unit |
| Verification result | Allergen verification record | Pass, fail and any re-clean |
| Overrun reason | Supervisor notes | Free text or a short code list |
- 01Your work records
- 02Personal details removed
- 03You approve the release
- 04Licensed to AI developers
How to build the matrix from actual run logs#
Building the matrix from actual run logs means pairing every product end with the next product start on the same line, then attaching the sanitation and verification records that fall between them. The steps below work in a spreadsheet before any software is involved.
Expect the first version to have gaps. Pairs that have never run show no history, and pairs that ran once show a single value. Mark those as estimates and let new runs fill them in.
- Export run logs by line with SKU, lot and start and stop times.
- Sort by line and time, and pair each run's end with the next run's start.
- Attach the sanitation record and verification result that fall between each pair.
- Look up each SKU's allergen class from the formula or specification system.
- Calculate actual changeover time from last good unit to first good unit.
- Group by line and product pair, and review outliers with the sanitation lead.
- Publish the matrix to planners and update it as new changeovers close.
Why allergen sequencing logic needs a record#
Allergen sequencing logic needs a record because it is the reason a schedule looks the way it does, and the reason is easy to lose. Running products without an allergen before products with one, grouping products that share an allergen, and scheduling full cleans at natural break points are common practices, but each plant and each brand applies them differently.
Food safety plans under FSMA may set allergen controls that shape sequencing, and many brand customers add their own requirements in the co-manufacturing agreement. Write the rules down beside the matrix, with the source of each rule, so a new planner or a scheduling tool can follow the same logic. Check your own food safety plan and customer requirements rather than relying on general practice.
What makes changeover data unreliable?#
Changeover data becomes unreliable when the start and end of the changeover are not recorded as separate events. The table lists the common failures and a fix for each.
| Problem | Effect | Fix |
|---|---|---|
| Changeover lumped into general downtime | Changeover time cannot be isolated | Add a changeover downtime code with from and to SKU |
| Clean type not recorded | Wet washes and dry cleans look alike | Make clean type a required field on the sanitation form |
| First good unit time missing | Restart time includes ramp-up scrap | Record when the first in-spec unit was produced |
| Brand renames or recodes SKUs | History splits across codes | Keep a SKU crosswalk by formula |
| Paper sanitation forms scanned as images | Times cannot be analyzed | Capture key fields digitally, keep scans as backup |
Illustrative: a snack co-packer replaces tribal knowledge#
Illustrative: a fictional co-packer runs bars and powdered mixes for several brand owners on three lines. Its ERP holds orders and lots, run times are typed into a spreadsheet by shift leads, and sanitation forms are on paper.
The plant manager adds a changeover code with from and to SKU to the run spreadsheet, moves the sanitation form to a tablet with clean type and finish time, and builds a matrix by line. The matrix shows that one powder line loses far more time switching between two brands' products with the same allergen profile than expected, because one brand's agreement requires a full clean every time. Planning starts grouping that brand's runs together.
When a scheduling software vendor proposes an AI sequencing pilot, the co-packer already has the changeover matrix and written sequencing rules the tool needs. The COO reviews the vendor's data terms before sharing any history.
Who controls changeover records at a co-packer?#
Changeover records at a co-packer are usually its own operating records, while the formulas, specifications and brand names belong to the brand owners. The co-manufacturing agreement decides the details, and some agreements restrict how the co-packer may use any information about the brand's products.
That split matters for any use outside the plant. Changeover times, clean types, verification results and sequencing rules can often be shared with brand identities and formulas replaced by allergen class and product family codes. Formulas themselves stay out unless the brand agrees in writing.
How SourceX approaches co-packer run and changeover records#
For a co-packer, SourceX opens the SourceX five-step transaction (Supply, Rights, Preparation, Approval, Delivery) by asking which systems hold run logs and sanitation records, how far back they go and whether each changeover names the products on either side. The co-packer keeps ownership of anything it later licenses.
Rights work centers on the co-manufacturing agreements. In preparation, brand names, formulas and employee details are removed or coded, and the co-packer approves the final scope. Its SourceX Evidence Packet then shows provenance, which brand agreements were checked, what use is permitted, how employee names were handled and who released the data.
Frequently asked questions
Should changeover time end at line restart or at the first good unit?
At the first good unit. Line restart includes ramp-up time, adjustments and scrap that belong to the changeover, and leaving them out makes changeovers look shorter than the schedule experiences. Record both if you can, and use first good unit for the matrix.
Do brand customers need to approve sharing changeover data?
It depends on the co-manufacturing agreement. Many agreements treat information about the brand's products as confidential, which can reach SKU names and run quantities. Changeover data recoded by allergen class and product family is less sensitive, but read the confidentiality clauses and ask the brand when in doubt.
Can ATP swab results stand in for allergen verification?
Not on their own in most programs. ATP tests measure general organic residue rather than a specific allergen protein, so many plants pair them with allergen-specific tests where their food safety plan calls for it. Record which test was used for each changeover so the matrix reflects the actual verification.
How detailed should clean types be?
Detailed enough that two cleans with different times and risks are never recorded as the same thing. Most plants use a short list, such as dry clean, wet wash and full allergen clean, plus a field for partial cleans on specific equipment. Avoid free text for the clean type itself.
Will an AI scheduling vendor own our changeover history?
Not unless the contract says so, but some vendor terms allow using customer data to improve their products. Read the data and AI clauses before a pilot, ask whether your history will train models used for other customers, and keep your own copy of the matrix outside the tool.
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