The difference is that they are more expensive. At CHOW’s local Safeway, one dozen Grade AA, extra-large white eggs from Lucerne sell for $3.19. Their brown counterparts, same size and grade, go for $3.98 per dozen. So why the higher price?

Hens that produce brown eggs are larger than white-egg-producing hens, and require more feed and care; that extra expense is passed on to the consumer. Although it might be cheaper to raise white-egg-producing hens, brown eggs continue to sell well, so they’re still a smart business choice for farmers.

It’s a widespread belief that hens with darker feathers and red earlobes produce brown eggs, while hens with white feathers and white earlobes produce white eggs. Kenneth E. Anderson, professor and poultry extension specialist at North Carolina State University, says it’s not an absolute rule, though he does acknowledge that most hens with white earlobes produce white eggs, and most hens with red earlobes produce brown eggs. Ultimately, eggshell color is a matter of a chicken’s genetics.

Hen breeds are predisposed to produce a certain color egg, says Clint Hickman, an owner of Hickman’s Family Farms. Which breed of hen will lay which color egg is pretty much well known in the industry: White Leghorns are the most popular breed used to lay white eggs, and Rhode Island Reds are most often used for laying brown eggs. (Check out this chicken chart to see what color eggs other hen breeds lay.)

CHOW’s Nagging Question column appears every Friday.