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Cooking and storing foods safely

Whether cooking for yourself or others, food safety is important. Germs in food can cause food poisoning. Food poisoning cases can vary from the mildly unpleasant to the very painful, and in rare cases it can kill.

Germs are so tiny that humans can't see them and they do not necessarily affect the look, smell or taste of food. Because we can't see germs, we need to keep all kitchen areas and cooking equipment clean and hygienic. And you should always wash your hands before handling food. Not just because you need to remove bacteria and germs that could make you ill, but also to remove dirt that could make food taste nasty.

Germs?
Treat 'em mean,
Keep it clean!

Germs multiply in warm, wet environments where they have access to oxygen so keeping food dry, cold (in the fridge) and wrapped up is a good idea. However germs are usually killed if thoroughly cooked.

Some foods need to be stored and prepared more carefully than others. Food that is wet, like meat and fish, can grow bacteria more quickly than dry food, and some foods are more likely to make you ill if not prepared correctly. Don't avoid any food because it needs careful preparation; just learn how to do it properly.

Carbohydrates

Most carbohydrates are easy to store and prepare but rice is one carbohydrate to be careful with. Rice grains may have spores of bacteria on their surface and these spores can survive cooking. If you eat cooked rice straightaway, you will be fine. But if you leave cooked rice standing at room temperature, the spores can germinate to give bacteria. The bacteria multiply and produce toxins that can cause vomiting and diarrhea. Reheating food will kill the bacteria but won't get rid of the dangerous toxins.

If you want to keep cooked rice for another day, or use it in a salad, cool it within an hour of cooking and keep it refrigerated until you want to use it. Don't keep cooked rice and grains for longer than two days and don't reheat them more than once.

Rice is nice, if you don't reheat it twice.

Fruit and vegetables

Fresh fruit and vegetables should be stored in a cool environment (not necessarily in the fridge) and eaten as soon as possible. Some vitamins and minerals are easily destroyed when fruit and vegetables are stored, chopped or cooked. To get the most nutrients from your five a day, try to follow these rules:

  • Eat fresh fruit and vegetables soon after you buy them. Tinned or frozen options can have more vitamins than fresh items that have been stored for a long time.
  • Don't leave cut vegetables open to the air.
  • Don't soak vegetables because vitamins and minerals can dissolve into the water.
  • Don't overcook vegetables.
  • Use as little water as possible when you cook vegetables.
  • Reuse the water you boil vegetables in (vitamins leak into the water) in a sauce or soup.
  • Eat hot vegetables as soon as they're ready because vitamin levels drop quickly.

Meat

It's very important to cook meat properly to make sure that any bacteria that could cause food poisoning have been killed. Bacteria can be found all the way through certain meat products (burgers, sausages, chicken, kebabs, other poultry, game and processed meats) so make sure you cook these until the juices in them run clear. Test the juices by pushing a fork into them. You can eat whole cuts of some meat (steaks, cutlets, joints) that are still pink inside, as long as they have been properly sealed/cooked on the outside. This is because any bacteria on these meats will be on the outside.

Store raw meat and poultry in clean sealed containers on the bottom shelf of the fridge, so liquid from the meat can't touch or drip onto other food. Check the 'use by' date of meat before you use it, and if the meat smells bad or hasn't been stored properly, throw it out!

If you have cooked meat and you're not going to eat it straight away, cool it as quickly as possible and then put it in the fridge. You can freeze cooked meat if you freeze it within 24 hours of cooking it.

You can also freeze raw meat providing you freeze it before the 'use by' date. When you want to use frozen meat, defrost it in the fridge so that it doesn't get too warm. When meat thaws, lots of liquid can come out of it. This liquid can spread bacteria so put defrosting meat in a container that catches the liquid so it can't touch other foods or contaminate surfaces. Use defrosted meat within two days of defrosting.

If you defrost raw meat and then cook it thoroughly, you can freeze it again, but never reheat foods more than once. Keep all cooked meat separate from raw meat.

Always thoroughly clean plates, utensils, surfaces and hands after they have touched raw or thawing meat, to stop bacteria from spreading. Always cook defrosted meat thoroughly.

Fish

Fish should be kept away from other foods and handled similarly to meat.

Shellfish can contain harmful viruses and bacteria so they should always be cooked properly. However oysters are eaten raw so these should be very fresh and come from an area where you know it is safe to eat oysters.

Always buy seafood that has been kept refrigerated or on ice. Once you've bought it take it home and refrigerate or freeze it as soon as possible. Don't buy frozen seafood if you see ice crystals through the packaging. This could be a sign that the fish has been thawed and refrozen.

To make sure you fish is safe to eat:

  • Keep seafood wrapped until it is ready to use.
  • Keep raw seafood away from cooked foods.
  • Don't store fish or shellfish in water.
  • Thaw frozen fish or shellfish in a container in the bottom of the fridge so any liquid that leaks out doesn't touch any other food.
  • Use separate cutting boards, knives, plates, etc. for preparing raw fish or shellfish.
  • Marinate seafood in the fridge and throw the marinade away after removing the raw fish or shellfish. If you want to use the marinade as a dip or sauce, set some aside before it touches the raw fish.
  • Throw away shellfish if their shells crack or break.
  • Cook fish so that the fat drips away.
  • Keep cooked fish or shellfish separate from raw fish and shellfish.

Eggs

Eggs in the UK are usually safe to eat. However some eggs can contain bacteria called salmonella and eating salmonella can make people very ill. If a whole egg, egg shell, or drips of egg white or yolk touch other foods, then bacteria can spread onto those foods. There could be bacteria on the egg shell, as well as inside the egg, so if you touch an egg, or get some egg on your hands wash and dry your hands thoroughly before touching other foods.

Always store eggs in a cool, dry place, such as the fridge, and keep eggs away from other foods. Don't use eggs after their 'best before' date and don't use eggs with damaged shells, because dirt or bacteria might have got inside them.

Eat dishes containing eggs as soon as possible after you've prepared them, but if you're not planning to eat them straight away, cool them quickly and then keep them in the fridge.

Pulses

Dried pulses need to be soaked and cooked before they are soft enough to use. Dried kidney beans and soya beans contain toxins so these need to be cooked properly before eating them. Tinned pulses are very quick and easy to use because they have already been soaked and cooked so you can use them straight from the tin.

Kidney beans contain a natural toxin (called lectin) that can cause stomachaches and vomiting. However, the toxin is destroyed if you prepare the beans properly. To make kidney beans safe:

  1. Soak the dried beans for at least 12 hours.
  2. Drain and rinse the beans then cover them with fresh water.
  3. Boil them vigorously for at least 10 minutes.
  4. Simmer the beans for 45 to 60 minutes.

Dried soya beans contain a natural toxin (which is called a 'trypsin inhibitor') that stops you digesting food properly. The toxin is destroyed if you prepare the beans properly. To make soya beans safe:

  1. Soak the dried beans for at least 12 hours.
  2. Drain and rinse the beans then cover them with fresh water.
  3. Boil them vigorously for 1 hour.
  4. Simmer the beans for approximately 2 to 3 hours to make them tender.

If you cook pulses and you aren't going to eat them immediately, cool them as quickly as possible and then put them in the fridge or freezer. Cooked pulses should be kept in the fridge and eaten within two days.