Bloated Paneer Pouches at a Nadia Dairy
A 200-litre-per-day paneer unit in Nadia packs 200 g pouches and sells through 12 retail shops. Milk is pasteurised on a plate HTST unit set at 72°C for 15 s. On 4 August the steam supply dropped and the chart shows 68°C for 11 minutes before the operator restored temperature. The paneer was then dipped in chilled chlorinated water (4°C, 50 ppm free chlorine), drained, packed in LDPE pouches and stored in shop refrigerators at 6–8°C. Three days later, 9 of 60 pouches were bloated. The laboratory found coliforms at 240 CFU/g, yeast and mould below 10 CFU/g, pH 6.4, and no Listeria. The owner says the milk supplier must be at fault because the milk was collected from 30 smallholders. He wants to reprocess the bloated paneer into sweets and sell it at a discount.
1. Decide whether the most likely source of the coliforms is the raw milk or contamination after pasteurisation. Support your judgement with two pieces of evidence from the record and state one additional record you would check.
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The most likely source is contamination after pasteurisation. Evidence 1: coliforms are vegetative, heat-sensitive cells; an 11-minute hold at 68°C is a substantial heat load and is unlikely to leave 240 CFU/g while yeast and mould remain below 10 CFU/g. A raw-milk failure would usually also show a high total bacterial count and a more mixed spoilage flora. Evidence 2: the high coliform count with normal pH and low yeast/mould points to contamination from the chill water, pouches, hands or poorly sanitised trays after heating. The 68°C excursion is still a serious CCP deviation and must be recorded and investigated, but it does not by itself explain the pattern. I would check the free-chlorine and change record for the dip water, the pouch-sealing record, and swab results for the packing table. The pasteuriser chart and divert record for 4 August should also be reviewed.
2. State the disposition of the 60 pouches and design corrective actions for the next batch. Include one verification activity.
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Disposition: condemn all 60 pouches, including the 9 bloated ones and the unbloated ones from the same run. Coliform contamination is not reliably removed by visual sorting, and converting the paneer into sweets would only spread the risk. Corrective actions: (i) record and investigate the pasteurisation deviation; (ii) divert or re-pasteurise any batch that does not meet 72°C/15 s; (iii) clean and sanitise the dip tank, crates, pouches and packing table; (iv) use potable chilled water with verified chlorine and measure free chlorine before each batch; (v) train handlers and enforce hand and foot hygiene and sealed-pouch checks; (vi) store at ≤4°C, not 6–8°C, and reduce time before dispatch. Verification: test the next three batches for coliforms and total plate count, and take environmental swabs of the packing table and dip tank; release only if coliforms are absent.