Five foods you should never cook straight from the freezer, Which? warns

Freezing remains a simple way to cut waste, preserve nutrients and save money, but health experts say not every food should be cooked straight from the freezer. Which? has identified five foods you should never cook without defrosting first, citing guidance from the Food Standards Agency (FSA) and its own testing. The advice aims to reduce the risk of uneven cooking and potential bacterial growth when foods are heated from frozen.

Raw chicken should never be cooked from frozen, according to the researchers. While processed chicken products such as nuggets can go straight into the oven, raw poultry must be defrosted in the fridge, a process that can take a day or more. Room-temperature defrosting is unsafe. Defrosted chicken should be cooked to a safe internal temperature, and leftovers should be handled properly.

Some sausages are sold frozen and may be cooked from frozen, but home-frozen sausages should always be fully defrosted before cooking. If you need to cook them immediately, use the microwave defrost setting; for later cooking, thaw in the fridge and ensure the centers are fully thawed before cooking.

Mince should also be defrosted before cooking. Blocks of mince are dense and can cook unevenly if they are still frozen, leaving parts undercooked and increasing the risk of food poisoning.

Prawns and other shellfish: while some packs are prepared to be cooked straight from frozen, most should be defrosted first. Cooking prawns from frozen can cause the outside to become tough while the centers stay cold, raising the risk of surviving bacteria. Thaw your prawns in the fridge overnight, or use the microwave's defrost setting if you are cooking them immediately.

Homemade frozen meals: batch-cooked dishes are convenient but can cook unevenly from frozen, especially layered dishes containing dairy or minced meat such as lasagne or cottage pie. The FSA says it is important to ensure the food is fully cooked and steaming hot the whole way through before serving.

Freezing remains a practical way to reduce waste and keep meals affordable, but safe defrosting is essential for poultry, meat, seafood and homemade dishes. When planning meals, consumers should check internal temperatures with a food thermometer and reheat foods only once, following official guidance.