Shell – the colour of the shell does not affect the nutritional value
Egg white – there are 2 types to the egg white, the thick and thin
Egg yolk – the colour of the yolk is related to what the hens are fed on. The yolk also contains lecithin which is an emulsifier. This is useful when combining ingredients which would normally separate, for instance when it is used in mayonnaise to prevent oil and water separating.