Australasian Science: Australia's authority on science since 1938

'Tis the season to get food poisoning

Research reveals food poisoning risk for the festive season, especially from raw egg dishes.

The Food Safety Information Council has released research results showing the increased risk of food poisoning from dishes that contain raw eggs. This could be a greater risk at Christmas as the weather hots up and we cater for several generations, including the very young and elderly.

Why is Christmas a greater time of risk from food poisoning?

  1. Christmas is the time of year we can be most at risk of food poisoning.
  2. With every increased degree of summer temperature the rate of food poisoning increases.
  3. The risk also increases when consumers cater for larger numbers of people using their domestic kitchen equipment, especially putting a strain on fridges.
  4. Consumers are also preparing food for several generations within a family including people who are at greater risk if they get food poisoning such as small children, pregnant women, the elderly and people with compromised immune systems.

How much food poisoning occurs in Australia each year?

  1. Food poisoning results, on average, in 5.4 million cases a year (including 120 deaths), 1.2 million visits to doctors, 300,000 prescriptions for antibiotics, and 2.1 million days of lost work each year.
  2. The estimated annual cost of food poisoning in Australia is $1.25 billion. A large majority of these cases of foodborne illness are single, sporadic infections.
  3. Norovirus, E. coli, Campylobacter and Salmonella are the most common pathogens that cause foodborne illness in Australia.

What is the food poisoning risk from raw eggs?

  1. This Christmas the Food Safety Information Council is focussing on the risk from dishes made from uncooked or minimally cooked eggs which can be a particular risk for food poisoning.
  2. Food Standards Australia New Zealand estimates there are about 12,800 cases of egg-related salmonellosis per year in Australia.
  3. OzFoodNet has shown that use of raw or minimally cooked eggs is currently the single largest cause of foodborne Salmonella outbreak. In their most recent 9 year survey period they have linked 68 food poisoning outbreaks to eggs with 1404 Australians ill, 322 hospitalised and 2 deaths.

What did a Food Safety Information Council consumer survey find?

  1. According to a national Newspoll survey, conducted for the Food Safety Information Council, almost one in five Australians are taking risks by not handling uncooked foods containing raw egg correctly.
  2. Almost 1 in 5 of those consumers surveyed did not know that homemade whole egg mayonnaise should be refrigerated straight away: with 9% incorrectly saying refrigerate after a few hours, 2% incorrectly saying it could be left out of the refrigerator overnight and 7% not knowing what to do at all.
  3. Raw egg dishes can include: egg nog, uncooked desserts such as tiramisu and mousses, sauces, fresh mayonnaise, hollandaise sauce, aoeli, health shakes with added raw egg or steak tartar.

What can consumers do to reduce the food poisoning risk from raw eggs?

  1. Dishes containing raw eggs as an ingredient, that aren’t going to be cooked before being eaten, should not be served to those vulnerable people at greater risk from food poisoning such as small children, pregnant women, the elderly and people with compromised immune systems.
  2. Egg meals should be cooked for these vulnerable people until the yolk in a boiled egg has started to become firm or eggs have become set in omelets or scrambled eggs.
  3. Check your eggs for visible cracks. If cracked it is safest to discard them or cook thoroughly, for example in a baked cake.
  4. If you accidentally drop pieces of shell into your egg mixture, it too could be contaminated and the mixture will need thorough cooking.
  5. Wash your hands with soap and running water and dry thoroughly before handling any food including eggs and after handling eggs or raw meat so you don’t contaminate other food.
  6. If you are not going to cook the eggs further, don’t separate the yolk from the white using the shell as that could contaminate the raw egg. Invest in a plastic egg separator.
  7. Prepare raw egg foods just before you are going to consume them and refrigerate immediately at 5°C or below, so the bacteria cannot grow.
  8. Keep your eggs refrigerated.
  9. If you have your own hens, gather eggs from their nesting places daily. Carefully check any eggs for cracks and wipe off any visible dirt with a dry cloth or paper towel but don’t wash the eggs. Then wash your hands with soap and water and dry thoroughly. If your children and grandchildren have been helping to collect eggs get them to wash their hands too.

Other food safety tips for Christmas

Ham
Christmas ham can keep several weeks with proper handling. After reading the instructions on the packaging, remove the ham from its plastic wrap, cover it with clean cloth or cotton bag soaked in water and vinegar, so it doesn’t dry out, and store it in the fridge below 5°C. Every few days rinse the cloth or bag in water and vinegar to refresh. Reduced salt hams are now becoming popular but may not last as long as conventional hams so follow instructions on the packaging. If purchasing an unpackaged ham direct from a butcher ask their advice on storage. Consider slicing any leftover ham, dividing into small containers and freezing for later use, for example on pizzas, in pastas etc.

Turkey
Check how many people will be eating turkey at your Christmas meal, you may only need to buy a turkey breast or a small bird which will be easier to defrost and not take up most of your fridge space. You can defrost a whole turkey in the fridge but this will take several days so it’s best to ask your butcher or supplier to defrost the turkey in their cool room. You must make sure it is thoroughly cooked all the way through to make sure any bacteria are killed – use a meat thermometer to check that the temperature in the thickest part reaches 75°C. Because stuffing slows down cooking and cooling, it is best cooked separately.

Seafood
Seafood is becoming more popular at Christmas time. Pick it up as close as possible to use. Bring it home in a cooler with ice and refrigerate promptly. If the seafood is going to be cooked this will kill any contamination caused by improper handling but there could be a risk if it is consumed raw (for example raw oysters, sushi, sashimi) or if precooked prawns are re-contaminated before serving. You will need to be particularly careful and hygienic in preparing these. Once again raw seafood isn’t recommended for vulnerable people like pregnant women, people with reduced immune systems, the elderly or young children.

The fridge
Before shopping for food for Christmas make sure there is enough room in the fridge to keep cold food at or less than 5oC. This is a good time to put the drinks on ice elsewhere and use the fridge to store perishable food. Make sure that raw meat and poultry can’t contaminate ready to eat food. Raw food can contain food poisoning bacteria. This is not a problem if the food is cooked before it is eaten. However, if these bacteria get onto ready to eat food, such as salads or desserts, they can cause food poisoning.

Leftovers
For some reason we always seem to end up with more food than we started with at Christmas Plan ahead for the number of people coming so you don’t end up with too many leftovers. Refrigerate any leftovers immediately after the meal, divide them into smaller portions or shallow containers if in large quantity, cover and place in fridge or freezer – they will cool quicker this way. Make sure there is good air circulation around the containers. Always store perishable leftovers in the fridge and use them up within two to three days. When reheating food ensure that it is steaming hot all the way through (at least 75°C).

Cross-contamination
Regardless of the number of people you are catering for, you need to be careful when preparing food to prevent any cross contamination from bacteria. Wash your hands, chopping boards, knives and anything else which will come into contact with the food before you start preparing and between preparing raw and ready to eat foods. When possible, prepare ready to eat foods (like salads, fruit and dessert) first and refrigerate. Then prepare raw foods like meat that will be cooked.

Temperature danger zone
Between 5°C and 60°C is known as temperature danger zone. This is because in this zone bacteria can grow to unsafe levels in this temperature range, Don’t leave perishable foods in this zone for more than 2 hours. Divide nibbles, like dips and soft cheeses into small amounts and replenish with fresh portions as required. This also makes them look more appetising. Don't mix fresh top-ups with ones that have been outside for some time.

Food Safety Information Council (http://www.foodsafety.asn.au)