The Chopping Board and the Raw Chicken
During a lunch service, a chef uses a red chopping board to prepare raw chicken, then wipes it with a cloth and places it back on the rack. Ten minutes later, another chef picks up the same board to slice cooked ham for sandwiches. The board looks clean. The kitchen has a colour-coded board system: red for raw meat, green for vegetables, yellow for cooked meat. The cloth used to wipe the board is the same one used earlier to wipe down the sandwich prep area. The dishwasher is running but the board was not put through it.
1. Identify the cross-contamination risks in this scenario and explain how they arise.
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The board was used for raw chicken and then only wiped, not washed and disinfected. Raw chicken juices can carry pathogens such as Campylobacter and Salmonella. Wiping spreads them across the surface and onto the cloth. The same cloth was used on the sandwich prep area, so contamination is transferred there. The second chef then uses the board for cooked ham, which is ready-to-eat, so pathogens on the board transfer directly to food that will not be cooked again. The colour-coding system has been defeated because the board was reused for the wrong food type without cleaning.
2. Explain the correct cleaning procedure for the board and the cloth, and the order in which tasks should happen.
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The board should be washed in hot soapy water to remove food and grease, then disinfected - either by immersion in a disinfectant solution at the manufacturer's concentration and contact time, or by running it through a dishwasher on a hot cycle. It should be air-dried, not wiped with a cloth. The cloth should be changed frequently; a cloth used on raw meat areas should not be used on ready-to-eat areas. Ideally use disposable cloths or colour-coded cloths. The sequence is: remove food debris, wash, rinse, disinfect, dry. The board should not return to the rack until disinfected, and the sandwich prep area should be cleaned and disinfected before further use.
3. What should the supervisor do now that the ham has been sliced on the contaminated board?
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The ham must be treated as contaminated and discarded - it will not be cooked again, so there is no kill step. The sandwich prep area and the cloth must be cleaned and disinfected. The supervisor should check whether any sandwiches have already been made with the ham and, if so, withdraw them. The incident should be recorded, the chefs retrained on the colour-coding system, and the cloth policy reviewed. The supervisor should also check whether the dishwasher cycle is adequate and whether boards are being put through it consistently.