Watch how we candle our eggs with our homemade egg candler. This is called “candling” because in earlier times, farmers would literally use a candle placed beneath the egg to try to see inside it. Non-fertilized eggs that we eat are also candled to determine their grade. High-tech machines with sophisticated lights can quickly determine the quality of the egg while it is still inside its shell. For our fertilized eggs, we are candling to see which eggs have viable embryos inside that will soon hatch into baby chicks.
Click here for an assortment of printable worksheets related to embryology, eggs, and chickens from University of Illinois Extension.