One board, one sink: chicken then school sandwiches in Birkirkara
A takeaway in Birkirkara has one stainless prep table, one white chopping board, one knife and a single two-bowl sink. At 11:30 the cook trims 8 kg of raw chicken breasts for the grill. At 11:45 he rinses the board and knife under the tap, wipes them with a reusable cloth that has been on the bench all morning, and sprays the board with a sanitising solution, wiping it once with a paper towel. He then uses the same board and knife to make 20 ham-and-cheese sandwiches for a school order due at 12:30. The sandwiches are stacked on a tray and covered with cling film. The cloth is hung back on the tap. The sink is then used to rinse lettuce for a separate order. The takeaway's written procedure says 'clean and disinfect boards between raw and ready-to-eat foods' but does not say how. The cook says the sanitiser 'kills everything in 30 seconds'.
1. Identify the cross-contamination routes in this sequence and say which is most significant for the school sandwiches.
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The main route is the reusable cloth. It has been on the bench during raw chicken preparation, so it is likely to hold chicken juice; it is then wiped over the board and hung on the tap, where it can contaminate hands, utensils and the sink. The second route is the board and knife: rinsing under the tap does not remove or kill bacteria, and a single spray-and-wipe may not give the sanitiser's required contact time, especially on a wet board. The third is the sink: lettuce is rinsed there after raw chicken, so splashes and contact with the sink surface can contaminate a ready-to-eat food. The fourth is hands and the bench. For the school sandwiches, the cloth and the inadequately cleaned board and knife are most significant because the ham and cheese will not be cooked before eating.
2. What should be done with the 20 sandwiches now, and why? Consider evidence and risk.
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Discard the 20 sandwiches. They are ready-to-eat, they were assembled on a board and with a knife that had just been used for raw chicken and then given only a rinse and a quick wipe, and a contaminated cloth was used in the process. You cannot make them safe by reheating: reheating a ham-and-cheese sandwich would not reliably penetrate and would ruin it, and it would not undo the cross-contamination. The risk is invisible; appearance and smell are not evidence of safety. Record what happened, tell the manager, and contact the school to explain that the order cannot be supplied. Do not offer the sandwiches to staff as an alternative. Review the takeaway's procedure and retrain the cook before the next service.
3. Rewrite the cleaning step as a workable procedure for a one-board kitchen, including what to do if a second board is not available.
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Workable procedure for a one-board kitchen: (1) Plan the order of work - make ready-to-eat items first, before any raw meat, or use a dedicated red board for raw meat and a white board for ready-to-eat if one can be bought. (2) If only one board is available, clean and disinfect it between tasks: scrape off debris, wash with hot soapy water, rinse, then apply a food-safe disinfectant at the correct dilution and leave it for the stated contact time; air dry or use single-use paper towels. (3) Replace the reusable cloth with single-use paper towels for raw meat areas, or use colour-coded cloths and change them after raw meat. (4) Wash hands after handling raw chicken and before touching the board, knife or sandwiches. (5) Do not rinse raw chicken under the tap; pat it dry with paper towel and discard. (6) Use a separate bowl for lettuce and disinfect the sink after raw meat. Supervise the first service and record the check.