Eggnog is a rich, creamy beverage made of milk, eggs, sugar and flavorings. It is most often served during the Christmas season. Brandy, rum, whiskey or some other alcohol is a common addition. Eggnog was traditionally made with raw eggs, but now raw eggs introduce a risk of bacterial contamination. Consequently, when preparing homemade eggnog, be certain to choose a recipe that uses a cooked egg custard base or use a pasteurized liquid whole egg product in place of raw eggs. Commercially prepared eggnog is made with pasteurized eggs, thus eliminating any danger of contamination. Eggnog is available in the supermarket dairy section from October through December.