Italians buy their eggs according to the color of the yolks. Yellow yolked eggs are labeled giallo dell’uovo, and the prized orange yolked egg is called (actually) red yolked egg, rosso d’uovo. I’ll do chemistry first, and then the backstory.
Since Dr. Leroy Palmer first published his research in 1915, it has been known that yolk color is caused by the chicken’s diet. Different carotenoids called xanthophylls are the determinants. More recent research has narrowed down the two main chemicals to Lutein and Zeaxanthin, and one scientist has determined the first is the source of the yellow yolked egg coloring, and the latter for the orange color. That led me on the search for the second one.
Veg! Feed the birds leafy greens, corn, wheat and carrots, as all are good supplements to the diet. This supports my observation that their favorite food is Dandelion greens. I can start a chicken riot with those every time.
Now to the backstory. I was fascinated by the great food book by Bill Buford called Heat. He became so fascinated with Italian food that he goes to Italy regularly to learn from the best of the best cooks. Even though he was the fiction editor for The New Yorker magazine, he was born in Mississippi, and knows his eggs. Hence his experience with a woman who is a legendary pasta maker in Italy.
Bill describes the master of pasta, and why he went to study with her:
It was also why I’d got so interested in the egg, because on my first morning, watching Betta prepare the dough, I saw that an egg was a modern pasta’s most important ingredient, provided that it is a very good egg, which was evident (or not) the moment you cracked it open. If the white was runny, you knew the egg had come from a battery-farmed animal , cooped up in a cage, and the pasta you made from it would be sticky and difficult to work with, exactly like the unhappy batch that Betta produced one evening after Gianni fell asleep, having had too much wine at lunch, and failed to buy eggs from the good shop before it closed and had to drive to the next town to the cattivo alimentarii, the nasty store, and pick up a dozen of its mass-produced product. The yolk was also illuminating. The nasty store’s were pale yellow, like those most of us have been scrambling for our urban lives. But a proper yolk is a different color and, in Italian, is still called il rosso, the red bit …Heat, Bill Buford
Poor urban folk, deprived of all the goodies. I have a mixture I now feed my birds. The basic bit is as follows:
16% Protein Organic Chicken Crumbles
Corn and Wheat Scratch
Black Oil Sunflower Seeds
Various Greens in Season
Other Fruit and Veg that are left over (Squash and Pumpkin are especially good)
Ours yolks just keep getting more and more orange. I may one day even get one of the legendary red tinged yolks.