Which component in egg yolk provides yellow color? Why might the color of yolk vary from one egg producer to another and throughout the season? Why do the FDA and the American Egg Board call eggs...

Which component in egg yolk provides yellow color? Why might the color of yolk vary from one egg producer to another and throughout the season?

Why do the FDA and the American Egg Board call eggs purchased in the shell “shell eggs” and not “fresh eggs”?