Pasteuriser deviation and release of 600 cups
A dairy fills 200,000 yogurt cups per day. The pasteuriser is a CCP with critical limits of 72 °C for 15 seconds; monitoring is every 30 minutes by the operator plus a continuous chart. On 14 March the chart shows 71.3 °C for six minutes at 02:10. The operator adjusted the flow-divert valve and resumed. Product from the affected period was diverted to a balance tank, but 600 cups had already been packed from that tank after a rework decision. QA released the 600 cups because a sample tested negative for coliforms. The deviation record was signed by a supervisor with no food safety team review. The pasteuriser had been serviced two weeks earlier, and the temperature controller had shown intermittent drift. No customer complaint followed.
1. Evaluate the release of the 600 cups. Was the negative coliform result sufficient? What should have happened under the FSMS?
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No, the release was not adequately supported. A critical limit exceedance means the product is a potential nonconforming product and must be handled under the control of product and process nonconformities. The first question is whether the product was actually re-pasteurised. Product diverted to a balance tank is not automatically safe: the tank may contain a mix of treated and untreated product, and the 600 cups may not have received the full 72 °C/15 s treatment.
A negative coliform result is not sufficient for release. Coliforms are not a validated indicator for the specific hazard in pasteurised yogurt, and a single sample has limited statistical power. The release decision needed a documented food safety assessment: time-temperature history, whether rework was validated, the hazard being controlled (e.g. vegetative pathogens), and the sampling plan. If the assessment could not demonstrate safety, the product should have been held and destroyed or reworked under a validated process. If it had been despatched, withdrawal/recall and customer notification would need consideration.
The supervisor's signature was also inadequate: the deviation should have been reviewed by the food safety team or a competent authority under the HACCP plan.
2. What corrective action is required? Distinguish correction, root cause analysis and verification of effectiveness.
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Correction. Contain the affected product, segregate it, record lot codes and quantities, and decide disposition. Restore the pasteuriser to control and revalidate the diverted/rework route if it is to be used.
Root cause. Investigate why the temperature drifted: the controller had shown intermittent drift and had been serviced two weeks earlier. Check the service record, calibration, valve response, alarm set-point, flow rate and whether the divert valve actually diverted all affected product. Also investigate why 600 cups were packed from the balance tank and why a supervisor could release without food safety review.
Corrective action. Fix the controller/valve, add or repair the alarm/interlock, revise the monitoring frequency or trend review, define who may authorise rework, require food safety team review of CCP deviations, and train operators and supervisors. Update the hazard analysis and HACCP plan if the rework route is now a controlled step.
Verification. Confirm the controller and divert valve perform correctly, review subsequent charts for drift, audit deviation records, and test whether the new authorisation rule is followed. The corrective action is not closed until effectiveness is verified.
3. What does this case suggest about the FSMS monitoring and record review, and what should management review see?
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The FSMS allowed a CCP deviation to be signed off by a supervisor without food safety team input, and allowed release on a single negative test. That suggests monitoring records were treated as production paperwork rather than food safety evidence. The 30-minute operator check plus continuous chart is only useful if the chart is reviewed, alarms are acted on, and deviations trigger a defined decision path.
Management review should see: the deviation, the quantity and disposition, whether any product reached customers, the root cause, corrective action status, and the trend in pasteuriser drift. It should also see whether resources and competence are adequate, whether the rework route is validated, and whether the recall/withdrawal plan was tested. The review should challenge why a supervisor had release authority and whether the food safety team is actually functioning. This is a test of the FSMS, not only of one operator's action.