How do I avoid cross-contamination when cooking?

The separation, sequence and cleaning habits that prevent raw ingredients contaminating everything else.

Difficulty: beginner
Time: 15 min
Read: 2 min
Safety: caution

Short answer

Keep raw meat separate at every stage — separate board, separate plate, bottom shelf of the fridge — and wash your hands and everything it touched immediately afterwards. Do not wash raw chicken; it sprays bacteria around the kitchen.

Cross-contamination is bacteria moving from raw food to something that will be eaten without further cooking. Every prevention measure is about separation in space, in time, or by cleaning in between.

Safety

Cross-contamination from raw meat, poultry, fish and eggs is a leading cause of food poisoning at home. Wash hands thoroughly with soap and warm water after handling raw meat, and never let raw meat or its juices touch food that will not be cooked.

What you'll need

Separate chopping boards
Soap and hot water
Kitchen paper (optional)

Step by step

Store raw meat on the bottom shelf of the fridge, covered.So nothing can drip onto food below it. This is the most common contamination route in a domestic fridge.
Use a separate board and knife for raw meat.Or do all your vegetable preparation first, then meat, then wash everything thoroughly.
Do not wash raw chicken.It does not remove bacteria and it sprays droplets up to a metre around the sink. Cooking is what makes chicken safe.
Wash hands with soap and warm water for twenty seconds after handling raw meat.Before touching anything else — taps, handles, phones, other food. Hands are the main vector.
Never put cooked food back on the plate that held it raw.A classic barbecue error. Use a clean plate for cooked food, always.
Wash utensils and surfaces immediately after raw meat.Hot soapy water. Wiping with a cloth that then wipes elsewhere spreads it rather than removing it.
Replace or wash cloths and sponges frequently.A damp kitchen cloth is one of the most contaminated objects in a house. Hot wash them regularly or use disposable paper for raw meat clean-up.
Cook to safe temperatures.74°C for poultry, 75°C for reheated food and minced meat. This is the final safeguard and the only one that kills what is present.

Tips

Prepare salads and anything eaten raw before handling any raw meat. Sequencing removes most of the risk without any extra washing.
Keep a bottle of soap by the sink specifically so hand-washing during cooking is frictionless.
Be particularly careful when cooking for anyone pregnant, elderly, very young or immunocompromised — the consequences are more serious.

Common mistakes

Washing raw chicken — It spreads bacteria in droplets around the sink and worktop, and does nothing that cooking will not do properly.
Reusing the plate that held raw meat — Any bacteria on it transfers directly to the cooked food, undoing the cooking entirely.
Wiping surfaces with the same cloth used on raw meat — It moves contamination around the kitchen rather than removing it.

Questions people ask

Should I wash chicken before cooking it?

No. Washing does not remove bacteria and it splashes droplets around the sink and worktops. Cooking to 74°C throughout is what makes chicken safe.

Where should raw meat go in the fridge?

On the bottom shelf, covered, on a plate or in a container. That way nothing can drip onto food stored below it.