When you freeze eggs and egg yolks, why do you have to add salt or sugar first?
Egg yolks or egg whites and yolks mixed will become grainy if frozen in that state. You can add sugar, corn syrup, or salt (depending on your ultimate use for the eggs) to prevent graininess. The eggs should then be strained through a sieve or colander before freezing. This will improve their uniformity. When freezing just whites, no salt or sugar is necessary. A good way to freeze eggs is to use ice cube trays. Put three tablespoons of the egg into each compartment of the tray, then freeze. When the cubes are frozen, place them in a moisture- and vapor-resistant container.