As much as we wanted to, we did not contact every eggnog maker in the country, but every one we did talk to said they only use yolks in their eggnogs, and the yolks are pasteurized before they go into the mix.

Pasteurization is a heating process, where the food is heated to a specific temperature and held for a certain period of time. The time and temperature varies from food to food, and some foods can be processed with different methods (milk, for example, may be heated to 150°F (66°C) for 30 minutes, 161°F (72°C) for 15 seconds, or in an ultra-high-temperature process, 280°F (138°C) for 1 to 2 seconds).

The time and temperature are calculated to ensure that most of the bacteria naturally present in the food are killed and to prolong the product's shelf life.