All Quality Assured eggs have a best-before date printed on the shell as well as on the egg box to ensure freshness. One simple test of freshness is to place an egg in water: generally, if the egg is stale it will float and, if it sinks, it is fresh. This is because as the egg gets older, the size of the air sac inside the egg, increases, making it float.
For optimum freshness and food safety, eggs should be kept at a constant temperature below 20°C. Most modern supermarkets are kept below 20°C so it is not necessary for retailers to store them in a fridge. This also prevents significant temperature fluctuations (for example eggs being moved from a fridge to a hot car after purchase).
For optimum freshness and food safety, eggs should be kept at a constant temperature below 20°C. To avoid the typical temperature fluctuations in a domestic kitchen, we recommend that eggs are stored in their box in the fridge.