Why Spike the Eggnog

 Science Eggnog Recipe

By Andrew DiMeo | 4 Minute Read

Rebecca Lancefield was a world renowned microbiologist at the Rockefeller Institute for Medical Research, which she joined in New York in 1918. In her more than 60 years at the University, Lancefield would publish over 50 manuscripts and become famous for her work in the classification of streptococcal bacteria, known as Lancefield Grouping.

But this time of year, what she may be remembered for is her eggnog, especially in the Bacterial Pathogenesis and Immunology Lab at The Rockefeller University. There, the tradition of her eggnog lives on since her passing in 1981.

Each year around Thanksgiving, Dr. Lancefield would spike a batch of eggnog in the lab, and then let it sit there for about a month to be enjoyed around Christmas. Letting the eggnog age in the cold of winter over those weeks between the holidays made it “better” according to her original recipe (below). But maybe what the microbiologist meant was, “better for your health.”

Afterall, eggnog calls for the use of raw eggs and to some that may be considered a bad idea due to the risk of Salmonella poisoning. Honestly today there’s little chance of getting Salmonella from a raw egg. However, that may have been different during Lancefield’s tenure through the early to mid twentieth century. She probably realized that alcohol would kill off harmful bacteria.

So the question is: Is spiking the eggnog really what kills the Salmonella?

This question was asked by Science Friday a decade ago. In 2008, they challenged the lab, led by Vincent Fischetti, to determine if spiking the eggnog is what made it safe to drink.

Fischetti and his group ran a small experiment (check out the Science Friday video here) by intentionally adding Salmonella to the eggnog. What they found was interesting. After a few days, one could see the level of Salmonella declining, but it wasn’t safe to drink right away. It was somewhere between 2 to 3 weeks that they observed the Salmonella completely eliminated from the eggnog.

I made the recipe a few years ago (with slight modifications), and thoroughly enjoyed it. Since, it’s become an annual tradition to make on Thanksgiving weekend and enjoy at Christmas.

If you want to make it yourself, here’s Dr. Lancefield’s Original recipe:

1 Doz Eggs
1 Qt H Cream
1 Qt Lt Cream
1 Qt Bourbon
1 Pnt Rum
Nutmeg (⅓ - ¾ box)
Sugar to taste (½ to ¾ Lb)

Beat eggs, add Bourbon and rum slowly with stirring to prevent precipitation of egg proteins.

Beat heavy cream separately ‘till peaks and add to the egg/bourbon/rum mix.

Add the light cream with beating. Add the sugar to taste with mixing (1 pound / batch) then Nutmeg.

Leave standing at least overnight with lid slightly ajar in refrigerator.

Better after 2-3 weeks in the cold.

 Science Andrew DiMeo Eggnog Recipe

This year I used 3 pints bourbon and no rum (because I don’t like rum), half/half in place of light cream (to slightly reduce the fat content… because it’s less fat… and healthier that way), and ½ pound of sugar (so that it’s not so sweet… because it’s less sweet… and healthier that way). I used only a couple teaspoons of Nutmeg (more can be added for taste when serving).

I’ll let you know how it turns out in about 3 weeks.