Food safety when cooking for others

When you cook for friends, you are responsible for their health as well as your own. A buffet left out too long in a warm room is one of the classic ways food poisoning spreads at gatherings.

The danger zone and the 2-hour rule

• Bacteria that cause food poisoning multiply quickly between 4C and 60C (40F and 140F), which US agencies call the danger zone.
• The FDA and CDC say perishable food should not sit at room temperature for more than 2 hours.
• If it is hotter than 32C (90F), the limit drops to 1 hour. That matters in the GCC: think of a beach picnic, an outdoor majlis in summer or food left in a hot car.
• After the time limit, throw the food away. You cannot see, smell or taste whether it has become unsafe.
• Write the time food came out on a sticky note by the dish if you are running a long buffet.

Keep hot food hot

• The FDA says hot food should be held at 60C (140F) or warmer. Use a food thermometer to check.
• Chafing dishes, slow cookers and warming trays can keep food hot, but the FDA warns that some warmers only hold food at about 43 to 49C (110 to 120F), which is not hot enough. Check the label.
• A low oven works well for keeping dishes warm until you serve them.
• If you cooked ahead and are reheating, the UK Food Standards Agency (FSA) says food must be steaming hot all the way through, reaching 70C for 2 minutes in the middle. US guidance gives 74C (165F) for reheated leftovers.
• For a big dish such as a biryani or lasagne, the FSA suggests checking for steam from the surface and then cutting into the centre to check for steam there too.

Keep cold food cold

• The FDA says cold food should be kept at 4C (40F) or colder. Keep salads, dips, desserts and fruit in the fridge until serving time.
• For a buffet that will run more than 2 hours, the FDA suggests setting plates of cold food on ice.
• Dress salads and add creamy sauces at the last moment, then put them out in smaller bowls you can refresh.
• Keep your fridge between 0 and 5C (FSA). If it is packed full before a party, use a cool box with ice packs for drinks to free up space for food.

Clean and separate while you cook

• Wash your hands with soap and water for at least 20 seconds before cooking and after touching raw meat, chicken, fish or eggs (FoodSafety.gov).
• Use separate chopping boards and plates for raw meat and for ready-to-eat food, and never put cooked food back on a plate that held raw meat.
• Wash boards, knives and worktops in hot, soapy water after raw meat.
• Use a thermometer or cut into the thickest part of chicken: no pink meat and clear juices (FSA).
• If you are ill with vomiting or diarrhoea, do not cook for others. Ask a friend to take over or postpone.

Rice and big batches need extra care

• Food Standards Scotland explains that rice can carry spores of Bacillus cereus that survive cooking. The longer cooked rice sits at room temperature, the more likely it is to become unsafe.
• Cool leftover rice as quickly as possible, ideally within 1 hour, spread out in smaller portions, then refrigerate.
• Large amounts of food cool slowly. USDA advises dividing them into shallow containers so they chill quickly.
• Do not put a whole hot pot of curry or rice straight into the fridge; split it into smaller containers first (FSA).