Sunlight affects egg quality

Free range eggs are a good source of dietary vitamin D, each egg from hens that spend most of the day outdoors contains about 10% of the required daily value . The vitamin D is concentrated in the yolk. along with most other nutrients such as folic acid. Research in Britain has indicated that when hens are exposed to direct sunlight, they tend to lay paler shelled eggs. All eggs are initially white, and shell colour is the result of the pigments called porphyrins being deposited while the eggs are in the process of formation. In the case of the Rhode Island Red, the brown pigment,derived from haemoglobin in the blood, is what gives the shell its brown colour. Araucana hens produce a pigment called oocyanin, which is a product of bile formation, and results in blue or bluish-green shelled eggs. There is no relationship between egg quality and shell colour. Nutritionally they are the same, but it's always surprising how many people still think that brown eggs come from free-range hens while white ones come from caged hens!The nutritional difference is a result of feed and free access to pasture, grubs and insects