Drinking year-old eggnog to put science to the test (2014)

Three-week-old eggnog and year-old eggnog look pretty much identical. Whether it's three weeks old or three years old, aged eggnog is actually safer to drink than fresh eggnog made with raw eggs-as long as you put plenty of booze in it. In 2009 microbiologists at the Rockefeller Institute for Medical Research decided to test their hypothesis that the alcohol would kill any bacteria in the eggnog they made in the lab every holiday season. Science Friday's Flora Lichtman, who's covered the Rockefeller experiments, said that the concentration of alcohol in the finished eggnog is 20 percent. A shot from last year of adding the brandy to the eggnog. Pretty much every article I'd read said that aged eggnog will continue to improve the longer you keep it-Ruhlman tried a two-year-old eggnog a few years ago and loved it-but I did find one blog post that disagreed. Last year Booze Nerds tried six different versions of the same eggnog recipe, fresh and aged for up to five weeks, with all the one-week intervals in between.