Before you make that delicious eggy in a basket, make sure you read our tips on how to purchase, store and consume eggs safely.
Before you go making your eggy in a basket, be sure to purchase and store your eggs correctly and safely. Image credit – Scott Feldstein/Flickr
Recently the national standard for free range egg production has undergone some changes. While the debate continues over the new standard rulings, it has served as a good reminder for safe egg consumption. There are lots of things to look out for when it comes to this incredibly versatile and protein packed food, so we’ve created a list to help you buy, store and consume eggs safely.
Safety tips
- Buy your eggs from supermarkets or shops which store them in the refrigerator or at least in a cool area of the store. Refrigerate your eggs immediately on arriving home – treat them like you treat your milk.
- If you make dishes in which the eggs are only lightly cooked, such as some sauces, serve the food immediately or refrigerate. Don’t let it stand around at room temperature.
- Any soufflés, egg nogs etc., containing raw eggs must be kept in the refrigerator until just before they are eaten. Avoid giving young children, the elderly and people with impaired immune systems foods containing raw or lightly cooked eggs.
- Observe good personal hygiene when preparing food; always thoroughly wash your hands before starting to prepare food and after handling raw foods.
Egg quality: what to look for when buying
If you look closely at an egg shell held against a bright light in a dark room you will be able to see an air gap, usually at the blunt end of the egg. In a fresh egg this air cell is quite small but as the egg ages, water is lost from the 17 000 pores in the egg and the air cell gets larger. Also you can see a large moving shadow in the egg which is the yolk floating about in the white.
In fresh eggs the yolk is small and in the centre of the egg. If you hard boil an old egg, you can quite clearly see the air cell indentation in the top of the egg, you can also identify if the yolk has moved off centre by cutting a hard-boiled egg lengthways.
Fast Facts:
- A quick test for freshness is to check if the raw egg in the shell sinks in a basin of water. Fresh eggs stay at the bottom of the bowl while stale eggs stand on end or float because of the large air cell.
- Good quality, fresh eggs display certain characteristics when broken out.
- The yolk is small and rounded and stands high in a thick, gel-like egg white which tends to stay compact rather than spread out over a wide area.
- As eggs age, the yolk becomes larger and flatter, until it eventually breaks.
- The thick egg white becomes thin and runny. By this time the egg will also have developed a stale odour and flavour.
Storing eggs: control the temperature
The easiest way to maintain eggs at high quality is to store them in cartons in the refrigerator as soon as possible after they are laid. Clean eggs, free of visible defects of the shell and contents, will then remain at high quality for up to three months and will still be as ‘fresh’ as eggs stored for seven days at room temperature. They can be stored for longer periods but the quality will begin to deteriorate noticeably. The cartons reduce water loss and help prevent flavours from other foods from being absorbed into the eggs.
When storing eggs it is important to only store clean, uncracked eggs. Keep dirty or cracked eggs separate to avoid contamination of the clean eggs, these eggs should also be used immediately or frozen as pulp. Under no circumstances should eggs for in-shell storage be washed as this removes the surface bloom and makes the eggs more susceptible to attack by microbes.
Egg safety: how to enjoy your eggs without getting sick
Eggs are similar to other protein foods such as meat, fish and poultry, in that they may be contaminated with microbes which can, if allowed to grow, cause food poisoning. Although Salmonella is easy to destroy in cooking (any food cooked uniformly to a temperature of 72 °C will be free of Salmonella), poorly handled eggs have caused many documented outbreaks. This is often the result of consuming eggs raw or only lightly cooked.
1st November 2016 at 8:51 pm
Eggcellent !!
Thank you CSIRO. This is very useful information.
Part of me is saddened that this more consumer based research might be the product of savage budget cuts. However, there are still so many mundane things like this that I would love to know and I’m really glad someone is taking the time to find out.
29th July 2016 at 7:07 am
72oC for how long, to kill Salmonella?
5th August 2016 at 9:08 am
Hi Agnieszka,
72°C momentarily will kill Salmonella in the majority of high moisture foods. Longer times may be required for drier food types or foods with higher fat content.
Regards,
Ellen
CSIRO Social Media
12th April 2016 at 11:29 am
How do you clean eggs if you don’t wash freshly laid eggs before storage? When they are laid, it often has particles of dried poo on it that cannot be removed without washing?
12th April 2016 at 3:29 pm
I’d like an answer to this too.
17th May 2016 at 9:11 pm
Eggs are VERY porous and absorb doors & bacteria very easy.
Farm eggs that have faecal matter need to be wiped ASAP with a slightly damp cloth only on the area needed. It is BEST to remove faecal matter from nest early EVERY morn before eggs are laid. Have plenty of straw in nest boxes.
I started raising chickens, geese, ducks & turkeys since I was 6 years old (1962). Every house I have bought ends up with chooks, including “rescued” battery hens. I never have animals in “CAGES”.
12th April 2016 at 8:10 am
I always leave warm fresh-from-hen eggs on the shelf to cool to air temp before putting them in the fridge. Is this silly? Should I put warm eggs straight into the fridge?
12th April 2016 at 2:16 pm
Better to put them straight in the fridge for quicker chilling; the longer food stays at room/body temperature, the more any bacteria proliferate and therefore the quicker the food ‘ages.’ Many species of bacteria love the temperature a hen would provide. The same principle applies for leaving food on the stove to cool – Much safer to chill quickly.
26th April 2016 at 11:52 am
Hi Steve,
It is safe to put warm eggs straight in the fridge once you collect them and they will stay fresh longer. Leaving eggs on the bench to cool before putting them in the fridge is OK – a few hours on the bench before refrigerating is not going to have a big impact on the safety but during this time there will be a loss in shelf life.
Cheers,
Ellen
CSIRO Social Media
11th April 2016 at 8:01 pm
Eggs boughg in supermarkets are washed by the producers. That seems to be contrary to the advice given. ??
26th April 2016 at 11:55 am
Hi Alimac,
Eggs can be washed by producers in preparation for retail sale under very controlled conditions; dry brushing can also be used instead of or in combination with washing. If eggs are washed it must be done with the correct use of detergents and sanitisers and under strict temperature control to ensure microorganisms present on the egg surface are not drawn into the egg (http://www.foodstandards.gov.au/publications/documents/Eggs_healthandsafety.pdf). For this reason, we recommend that consumers do not wash eggs at home and that they use any cracked or dirty eggs in dishes such as cakes that are going to be fully cooked so any bacteria present are killed.
Regards,
Ellen
CSIRO Social Media