Whilst Eggs don't last very long in my house, sometimes there is an excess and the order of what's new and old gets lost along the way. I love poached eggs but one of the keys to what makes a good poached egg great is the freshness.

This little trick is about as old as chickens have been around, or eggs, whichever came first....

Put an egg in a glass of water and it will give you a gauge of how old it is.

If it lays flat, it's about as fresh as you can get short of having chickens in your garden.
The more it starts to lift, the older it is. 

If it stands vertical, its weeks old. This will make a very bad poached egg!!