By Amanda Hoh
How fresh do your eggs need to be to poach them? And how long can you keep eggs before throwing them out?
Eggs are one of the many staples in our diet, but also one of those foods where any change in its structure or age will affect how it cooks and how safe it is to eat.
Gary Kennedy from food standards consultancy firm Correct Food Systems and Rob Peffer, an egg producer from Molong in New South Wales, gave 702 ABC Sydney
Should eggs be stored in the fridge?
It is recommended that eggs are stored in the refrigerator to make them last longer, although a cool pantry can also be suitable.
As an egg ages its enzymes start breaking down the protein structure of the egg white and so keeping them cold means the proteins will last longer.
“The biggest problem for eggs is going up and down in temperature,” Mr Peffer said.
“If you put them in the fridge then pull them out and leave them at 24 degrees and they sweat, that’s worse for the eggs than staying at a stable 18 to 20 degrees.”
Eggs will also last longer if they have been stored in the fridge at the supermarket and then at home.
When should you throw out eggs?
Eggs can last for about six weeks after they are laid, Mr Kennedy says.
After that time the egg “doesn’t perform as well”.
The white might be runny, for example, or will not form firm peaks if you are whipping the egg to make a pavlova or meringue.
What do the numbers stamped on eggs mean?
Some smaller farms like Mr Peffer’s may stamp their eggs with the laying week.
Other producers use extensive coding which could indicate the farm and what shed the eggs came from.
The industry standard is that the stamp identifies the egg grader — the person who sorts the good eggs from the bad ones, Mr Kennedy said.
“If there was any problem anywhere in the system, you could trace the egg all the way back to the farm, to which supermarket it was delivered to.”