I've heard that nitrofurans were found in chicken – what are they?

Nitrofurans are veterinary medicines that were used to treat some infections in animals. However, since 1995 they have been banned from use in food-producing animals in the European Union. This ban was introduced because of concerns that people could have a greater risk of developing cancer if they eat food containing nitrofurans over a long period. Countries wishing to import animal products into the EU must guarantee that they are free from nitrofurans, or contain levels below an agreed EU testing limit.

In the past couple of years, nitrofurans have been found occasionally in some food, including chicken, and the affected food has been taken off sale. This led to the EU bringing in temporary compulsory testing of these products from the countries the affected food came from, until the problem was resolved.

How much protein do I need each day?

Protein is essential for growth and repair of the body, and 15% of the calories we eat each day should come from protein. If you're eating a balanced diet you're probably getting enough protein.

Men need about 44 to 55g a day and women need about 36 to 45g protein each day.

Children also need plenty of protein to help them grow and how much will depend on what they weigh. As a general guide:

• children aged 4 to 6 need about 15 to 20g protein each day
• children aged 7 to 10 need about 23 to 28g protein each day

Most adults and children in the UK have more protein than they need.

The following foods are all good sources of protein:

• poultry (an average portion of roast chicken breast contains 27g protein)
• lean meat (an average portion of bolognese sauce contains 28g protein)
• fish (a small can of tuna and an average portion of poached cod fillet each contain 24g protein)
• cheese (an average cheese sandwich on white bread contains about 17g protein)
• eggs (an average-size boiled hens' egg contains about 6g protein)
• milk (a 150ml glass of semi-skimmed milk provides about 5g protein)
• pulses (three tablespoons of boiled red lentils contains about 9g protein)
• tofu (100g tofu contains about 23.5g protein)
• bread (a slice of wholemeal bread contains about 3g protein)

Don't forget that you need a healthy balanced diet including:

• meals based on starchy foods, such as bread, rice, pasta and potatoes – these types of foods should make up about a third of the food you eat
• lots of fruit and vegetables, also making up about a third of your diet – aim for at least five portions of a variety of fruit and veg each day
• some meat, fish, eggs or pulses
• some milk and dairy products, such as yoghurt and cheese, choosing lower-fat varieties when you can

It can be harder for vegetarians, and especially vegans, to get enough protein. So if you're vegetarian, try to eat a mixture of foods that are rich in protein every day, and vary the types you choose. For example, you could eat:

• pulses, such as lentils, beans and chickpeas
• nuts and seeds
• eggs
• soya products, such as tofu, miso and soya drinks
• mycoprotein, sold as Quorn^TM
• wheat proteins, such as cereals, bread, rice and maize
• milk and dairy products

Is overcooked or burnt meat carcinogenic?

Cooking meat and meat products, such as sausages, until they are overcooked or burnt can cause a number of chemicals to be formed, such as polycyclic aromatic hydrocarbons (PAHs) and heterocyclic amines (HAs).

PAHs are also found in the environment because they are produced when fossil fuels or refuse are burnt. And they are in tobacco smoke and vehicle exhaust emissions, too. Once these chemicals have been formed, they don't break down easily, and they are present at low concentrations in most foods. So, people take in small amounts of PAHs through their normal diet.

PAHs and HAs are formed when food is cooked at high temperatures (over 150°C), for example, by grilling, barbecuing or pan-frying. HAs only form in meat, poultry and fish, but PAHs may also be formed in other foods.

Some PAHs and HAs have been shown to cause cancer in animals, and we think they do this by interacting with DNA (basic genetic material). Chemicals that act in this way are called genotoxins. Some PAHs are also known to cause cancer in humans. At the moment we don't know if HAs cause cancer in humans, but we think they might play a role.

It isn't possible to establish a safe level of consumption for genotoxins but independent experts advise that intakes should be as low as possible.

You can reduce the amount of PAHs and HAs formed when you cook meat by doing the following things:

• choose lean meat and fish
• don't let flames touch food when you're barbecuing or grilling
• cook at lower temperatures for a longer time

Although overcooking meat may produce harmful chemicals, it's very important to make sure you don't undercook meat. Otherwise, any bacteria in the meat could survive and cause food poisoning. It's especially important to make sure that chicken and minced-meat products, such as burgers and sausages, are steaming hot all the way through with no pink meat left. And any juices should run clear.

When you're barbecuing, you're more likely to cook food properly if you cook it evenly over a steady heat. If you cook it over flames, it could be burnt on the outside and raw in the middle. Wait until the charcoal is glowing red, with a powdery grey surface, before you start to cook.

How should I defrost my Christmas turkey?

It's very important to defrost turkey thoroughly before you start cooking. You can check for this by:

• looking for ice crystals in the cavity
• testing thicker parts of the turkey with a fork to see if it feels frozen

Remove the packaging and put the turkey on a large dish to hold the liquid as it thaws. If you remove the giblets and the neck it will speed up thawing. As the turkey thaws, pour the liquid away regularly so it doesn't overflow and spread bacteria. But be careful not to splash it onto other food, surfaces etc.

You can defrost turkey by putting the dish in a cool, clean place (ideally the fridge) where the turkey won't touch other foods. If it isn't possible to defrost your turkey in the fridge, you can defrost it in a cool room.

Remember that the temperature of the place where the turkey is kept will affect thawing times. If you defrost your turkey in a cool place, such as the garage, watch out for sudden extremes in temperature. If it gets very cold, this could mean the turkey won't defrost properly. Keep the turkey covered and make sure that pets and young children are kept away.

You can also defrost your turkey at room temperature, but make sure it doesn't touch or drip onto other foods (and make sure you cook it properly).

Rough thawing guide
Per kilogram allow approximately:
10 to 12 hours in a fridge at 4°C/39°F
3 to 4 hours in a cool room (below 17.5°C/60°F)
2 hours at room temperature (about 20°C/68°F)

And always remember to wash your hands thoroughly before and after handling raw turkey so that bacteria doesn't spread to other foods you are preparing.

Is it OK to freeze fresh meat? Is there different advice for different types of meat?

It's OK to freeze fresh meat providing you do the following things:

• freeze it before the 'use by' date
• follow any freezing or thawing instructions on the label
• defrost it in a microwave if you intend to cook it as soon as it's defrosted, otherwise thaw it in the fridge so that it doesn't get too warm
• try to use the meat within two days of defrosting – it will go off in the same way as fresh meat
• cook food until it's steaming hot all the way through

Always cook chicken and minced-meat products such as sausages and burgers until the juices run clear and there's no pink meat.

When meat thaws, lots of liquid can come out of it. This liquid will spread bacteria to any food, plates or surface that it touches. Keep the meat in a sealed container at the bottom of the fridge so that it can't touch or drip onto other foods.

Always thoroughly clean plates, utensils, surfaces and hands after they have touched raw or thawing meat.

If you defrost raw meat and then cook it thoroughly, you can freeze it again, but remember never reheat foods more than once.

This advice applies to all types of meat and poultry.

How should I cook ostrich and venison?

Meat that is minced, skewered or rolled should be cooked until it's steaming hot all the way through and none of the meat is still pink, regardless of what type of meat it is.

Venison can be served pink in the middle, if it's a whole cut. Ostrich should not be served rare because it's considered to be like poultry. Make sure it's steaming hot all the way through with no pink meat left.

If you're cooking any meat and you're not sure whether it's OK to serve it rare, play it safe and cook it thoroughly.

Is it OK to eat rare steak and lamb that's pink inside?

Meat can become contaminated with bacteria during slaughter and processing. For whole cuts of meat, such as steaks, cutlets and joints, any bacteria are generally on the outside of the meat. If the outside is cooked, this should kill any bacteria, even if the middle of the meat is pink. This means you can eat whole cuts of beef and lamb when they are pink or rare, if you would like to.

But bacteria can be found all the way through minced-meat products, such as burgers and sausages, because of the way they are made. This is why it's important to cook sausages and burgers until any juices run clear and there's no pink meat left.

Poultry and game, such as chicken, turkey, duck and goose, can also contain bacteria, so they should be cooked until there's no pink meat left and any juices run clear.