Chocolate does expire over time, though high sugar content and low moisture help it remain edible past its printed best by date. Dark chocolate typically lasts for two years if stored properly in a cool and dry location, while milk and white chocolate last for about one year due to dairy ingredients. Exposure to heat or air can cause fats to bloom, creating a harmless white coating on the surface. Checking for unusual odors or mold helps determine if older chocolate is still good to eat.