- Julia Thiel
- Three-week-old eggnog (left) and year-old eggnog (right) look pretty much identical.
Aging eggnog for a few weeks sounds a little dicey. Aging it for a year sounds insane. The perishable parts of eggnog—milk, cream, eggs—could easily last a few weeks if properly refrigerated. But how many people have voluntarily consumed year-old milk and eggs?
The ratio of alcohol to other ingredients matters for sterilization, of course. Science Friday’s Flora Lichtman, who’s covered the Rockefeller experiments, said that the concentration of alcohol in the finished eggnog is 20 percent. But when Cook’s Illustrated tested out the recipe, they found that it was 14 percent alcohol, which matches up pretty well with the 13.5 percent ABV that I calculated (I assumed that they used 80-proof alcohol and large eggs).
I later tried a toned-down version of each version (two parts eggnog to one part milk/cream mixture), which allowed the flavors of the more aged eggnog to come through better. By comparison, the three-week-old eggnog actually seemed a little flat—very creamy, but with less complexity than the more aged version. They’re both very good (in small quantities), but I’d probably add a little less milk and cream to the younger one.
