Quality Control Guide
Freeze-Drying Batch QC Checklist
This is the full batch checklist, organized into four moments: before you start, while the cycle runs, before packaging, and after packaging. It is printable, and it turns a batch from a hope into a record.
Use this structured checklist around every batch: before, during, before packaging and after packaging.
The Quality-Control Principle
Quality control connects the food, the process and the record: batches are dried, checked, identified, packaged and documented so results are repeatable and problems are findable.
Before the Batch
Set the batch up to succeed:
- Food condition checked: sound, fresh or properly stored, not spoiled or questionable.
- Preparation complete for the food type (washed, cut, cooked or raw as decided).
- Trays clean, dry and correctly loaded.
- Correct batch identification assigned for this product and date.
- Equipment condition reviewed: pump oil level and condition, gasket, valves, seals.
- Machine area clean and ready; drain clear.
During the Batch
Observe without unnecessary chamber opening:
- Vacuum reached and held per machine expectations.
- Abnormal noise, vibration or alarms noted and investigated.
- Cycle interruption or unexpected behavior recorded.
- Unusual product behavior (collapse, splatter, boil-over) noted for review.
Do Not Open the Chamber Unnecessarily
Opening the chamber mid-cycle lets moisture and air back in and extends drying. Record what you can observe from outside and follow your machine manual for anything that needs intervention.
Before Packaging
The final gate:
- Dryness confirmed on the largest, densest pieces.
- Texture matches expectations for the food type.
- Package readiness: bags, jars, absorbers and labels ready.
- Work area clean and dry.
After Packaging
Close the loop:
- Heat seal inspected: clean, continuous, no gaps.
- Label correct: product, batch, weight, storage notes as applicable.
- Net weight recorded if relevant for the package.
- Oxygen absorber confirmed inside and active per its handling guidance.
- Package integrity: no punctures, no weak seams.
- Batch record completed and stored.
Batch Information
Frequently Asked Questions
Do I need to check everything on every batch?
Most checks are quick habits. The machine-condition checks (pump oil, gasket, valves) can be confirmed less frequently or per your maintenance schedule, while food and packaging checks matter on every batch.
Should I open the chamber to check during the cycle?
Generally no. Opening the chamber mid-cycle lets moisture and air back in, and draws out the cycle. Record what you can observe from outside and intervene only per your manual.
Key Takeaways
- Check food, trays, batch ID and equipment before you start.
- Observe the cycle from outside and record anything unusual.
- Verify dryness and package readiness before sealing.
- Inspect seals, labels and package integrity after packaging.
Related Guides
Continue through the Quality Control Center with these related guides.