Production
Checking pH on a batch
How to set a pH check up once and record it on every batch: the product's target pH, the recipe's pH measurement, what happens when a reading is out of range, and correcting a reading later.
pH is usually the check that matters most on an acidified product like a hot sauce, so it belongs in the recipe rather than on a clipboard. Set it up once and every batch asks for the reading at the right step, checks it against your range, and keeps it on the batch record.
Before you start
You'll need:
- A product with a recipe. See Creating a product.
- Your pH meter set up as equipment (for example "Bench pH meter, PH-001"), if you want the reading tied to the instrument that took it. See Setting up your equipment.
Record the product's target pH
Open the product, expand Food safety and fill in Target pH. If acidification is one of the product's preservation methods, also tick pH control (acidification) under Preservation methods. Then click Save.
These describe the finished product. Crown uses them in your food-safety work, including the hazard analysis, so they should match how you actually make it. They don't check any batch on their own: the recipe does that.
Add a pH measurement to the recipe
Open the recipe and go to the stage where the reading is taken (for Habanero Hot Honey, after the vinegar and honey are blended and before filling). Add a Measurement item:
- Measurement purpose: Generic.
- Parameter name: pH.
- Unit: pH.
- Min value / Max value: the range a batch has to land in, for example 3.4 to 3.8. Use the limits your process is built on; Crown doesn't suggest them.
- Monitoring method: By type (any pH meter), Specific unit (one meter, such as PH-001) or Test method / kit (pH strips), so the record shows what took the reading.
- CCP: tick it if pH is a critical control point in your food safety plan. Whether it is one is your decision.
Save the recipe and approve the new version. Batches started from then on ask for the reading; a batch already started stays on the version it began with. See Adding ingredients and steps for every measurement field.
Take the reading during a batch
When the batch reaches that stage, the operator enters the reading on the pH item. Crown checks it against the range straight away:
- In range: the step completes as normal.
- Out of range, not a CCP: Crown shows an amber "Value is outside expected range." The step can still complete with the reading as entered.
- Out of range on a CCP: the complete button becomes a Deviation button. The operator must log a deviation before going on, and the out-of-range result can't be dismissed.
More on working through a batch's steps is in Recording production steps.
Correct a reading after the batch
Once the batch has left production, a recorded pH reading gets an Amend value action. Enter the corrected number and a reason. The original and the correction both stay on the batch's audit trail.
If the true reading can't be recovered, leave the corrected value empty and the record shows no value rather than a wrong one. You can't add a reading that was never taken, and you can't move a CCP reading out of range, or clear one, without a deviation to account for it.
pH from a lab
A pH result from an outside lab is a lab test, not a batch step. Add pH as a parameter on a QC spec template with its range; Crown marks each result pass, fail or marginal and you make the final call. See Lab testing a batch.
What's next
- Logging a deviation: what to record when a reading is out of range.
- Releasing a batch: releasing the batch once its lab results are in.
Frequently asked questions
Where do I set the pH a batch has to hit in Crown QMS?
On the recipe, not the batch. Add a measurement item named pH to the stage where you take the reading and give it a minimum and a maximum. Every batch made from that recipe version then asks for the reading and checks it against that range.
What happens when a pH reading is out of range?
It depends on whether the measurement is marked as a critical control point. On a CCP, Crown replaces the complete button with a Deviation button and the operator has to log a deviation before going on. On any other measurement, Crown shows an amber warning and still lets the step complete.
Can I fix a pH reading that was typed in wrong?
Yes, once the batch has left production. The recorded reading gets an Amend value action; you enter the corrected number and a reason, and both the original and the correction stay on the batch's audit trail.
Is the target pH on the product the same as the recipe's range?
No. The product's target pH describes the finished product and feeds your food-safety records. The range on the recipe's pH measurement is what each batch is checked against on the floor. Set both.