One Board, One Cloth, Raw Chicken and a Ready-to-Eat Salad
A small restaurant in Port Harcourt serves 40 covers a night. The kitchen has one stainless steel prep table, one wooden cutting board and one sink. At 6 p.m. a cook cuts 8 kg of raw chicken on the board, then wipes the board with a damp cloth and uses it to chop lettuce, tomatoes and onions for salad. She rinses the knife under the tap for a few seconds. The cloth is used later to wipe the table and the salad bowl. The salad is held in a bowl on the counter at 28°C for 90 minutes before service. A server with a healing cut on her finger tosses the salad with bare hands. The restaurant has no sanitiser, and the cloth is rinsed and reused the next day.
1. Map the cross-contamination routes in this kitchen and rank them by risk. Explain why the absence of a cooking step changes the assessment.
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Routes: (1) raw chicken juice on the board transfers to lettuce, tomatoes and onions, which are eaten raw; (2) the damp cloth moves juice from the board to the table, the salad bowl and later the salad; (3) the knife rinse is not washing and does not sanitise, so it carries juice to the salad; (4) the server's healing cut can add S. aureus; (5) holding salad at 28°C for 90 minutes lets any contamination multiply.
Ranking: the board and cloth are the highest risk because they directly inoculate ready-to-eat food with raw poultry juice; the hands are next because bare-hand tossing distributes contamination; the knife and bowl follow. The warm hold is an amplifier rather than a source. The critical point is that salad receives no cooking step, so anything that reaches it survives.
This is a classic cross-contamination chain: raw food → surface → ready-to-eat food, with time-temperature abuse making it worse.
2. State a correct cleaning and sanitising sequence for the board and knife, and set out a practical colour-coding and cloth-control plan for this kitchen.
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Sequence for the board and knife: scrape off food debris; wash with hot water and detergent, using a brush for the wood grain; rinse; sanitise with an approved food-contact sanitiser at label dilution (for chlorine, commonly around 100 ppm) for the stated contact time; drain and air-dry. Wooden boards that are cracked, deeply scored or cannot be dried should be replaced. A two-stage wash is not optional after raw poultry.
Practical plan: buy two colour-coded boards - one for raw meat, one for ready-to-eat foods - and separate knives; if only one board exists, wash and sanitise between tasks, never just wipe. Use single-use cloths or launder cloths hot and dry them; do not use the same cloth for raw juice and the salad bowl. Put a sanitiser bucket and clean cloths at the prep table. Keep salad covered and cold (5°C or below) and out of the 28°C counter hold.
3. What immediate corrective action should be taken for the salad and for the server with the healing cut?
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Discard the salad. It is ready-to-eat, was tossed with bare hands by a server with a healing cut, was wiped over by a contaminated cloth and was held at 28°C for 90 minutes. There is no cooking step to reduce the contamination, and the cost of discarding is far lower than the cost of an outbreak.
Move the server away from ready-to-eat food until the cut is covered with a waterproof dressing; if she continues in the kitchen, she should wear a clean glove over the dressing and wash hands before gloving. Better, use tongs or a serving scoop so no bare hands touch the salad. Clean and sanitise the bowl, table, board and knife; replace the cloth; check the handwash point. Record the corrective action and retrain staff on raw/ready-to-eat separation. If anyone who ate the salad develops vomiting or diarrhoea, report it and keep the record.