Nothing is just "considered" Kosher. For the observant all foods must be certified Kosher. Eggs, for example, must come from farms that segregate (at all times) roosters and hens (to lessen the chance of a fertilized egg being sold). Any egg must be examined after cracking to determine if it has a blood spot. Brown eggs can be Kosher, but they run a higher discard rate since the brown outside coloring can cause small discolored spots on the inside, in which case the egg must be discarded...