Our resident food expert spills the history of his favorite creamy holiday libation.

• Eggnog is technically stirred custard—a mixture of dairy and eggs. It’s almost identical to ice cream, except that in most cases it contains too much alcohol to freeze.

• Although it can be cooked to kill off any possible salmonella and to thicken the mix, such thermal activity also deactivates the egg enzymes that give “real” eggnog its je ne sais quoi.

• As far back as the late 17th century, the term “nog” referred to a style of strong beer brewed in East Anglia, while a “noggin” was a small cup or mug that could be used for imbibing nog.

• Most culinary anthropologists believe modern eggnog descended from a thick, boozy, late-medieval concoction called posset that was composed of hot milk and hooch enhanced with whatever spice the lord of the castle had on hand.

• Egg-based drinks found new popularity in the American colonies, where nearly everyone had access to cows, chickens, and rum.

Nutritious and relatively stable, eggnog was our first health drink. If you ask me, sipping it is our patriotic duty.

• Although bourbon is the modern nog spirit, rum was the liquor of choice in colonial days.

• Today’s serious nogsters are into aging. After nog spends six months to a year in the fridge, a curious chemical collusion takes place as egg proteins, alcohol, and milk sugars slowly join forces. The resulting elixir tastes not of eggs, milk, sugar, or booze but simply of eggnog.

• Don’t worry too much about safety. As long as your brew contains at least 20 percent alcohol and is stored below 40°F for at least a month, any microbial nasties that might haunt your innards should be nice and dead.

Alton Brown’s Nog of Ages

Recipe courtesy Alton Brown, 2012

12 large chicken eggs (see note)

1 pound sugar

1 pint half n half (see the other note)

1 pint whole milk

1 pint heavy cream

1 cup jamaican rum

1 cup cognac

1 cup bourbon

1 tsp freshly grated nutmeg (plus more for serving)

1/4 tsp kosher salt

• Separate the eggs and store the whites for another purpose

• Beat the yolks with the sugar and nutmeg in a large mixing bowl until the mixture lightens in color and falls off the whisk in a solid “ribbon.”

• Combine dairy, booze, and salt in a second bowl or pitcher and then slowly beat into the egg mixture.

• Move to a large glass jar (or a couple of smaller ones) and store in the fridge for a minimum of 2 weeks. A month would be better, and two better still. In fact, there’s nothing that says you couldn’t age it a year but I’ve just never been able to wait that long.

• Serve in mugs or cups topped with a little extra nutmeg grated right on top.

Note on eggs: Although my research tells me it’s very likely the alcohol will kill off any microbial baddies present from the eggs, if you have any doubts at all or if you’re going to be serving the elderly or someone with an immune disorder, buy yourself some peace of mind and simply use pasteurized shell eggs. They’re available these days at most mega-marts.

Note on dairy: I’m super picky about the texture of my eggnog and find that the combination listed gets me what I’m looking for. That said, if you don’t want to bother (or if you’re not as picky) just go with a quart of half and half and call it a day.

And one more note: Yeah, it’s a lot of booze but the longer the nog ages, the more mellow it will get.

This story originally appeared in mental_floss magazine. Now go download our new iPad app! Or get a free issue of mental_floss magazine via mail. Want more Alton? Check out his recipes at mentalfloss.com/alton.