You’re not supposed to eat old eggs. Or drink milk that’s been sitting around for—oh, say, a year or two. So two-year-old eggnog sounds like a pretty bad idea. But there’s a loophole, it turns out. Alcohol is the key (as is so often the case): it kills any bacteria that may be lurking in the perishables, making the eggnog safer to consume than it would have been when fresh.
The one-year-old and two-year-old eggnogs didn’t taste radically different from one another—but both lacked the alcoholic bite I remembered from the year-old stuff I’d tasted last year. Instead, the 2013 vintage had acquired a subtle but slightly metallic flavor I disliked (I’d say that was the power of suggestion from a post I read last year about a metallic flavor in five-week-old eggnog, but I’d completely forgotten about the article until I came across it again yesterday). A friend who was tasting with me didn’t notice a metallic flavor in the older eggnog, but did think that the 2014 version tasted unpleasantly eggy—something I didn’t detect. She preferred the 2013 eggnog; I liked the 2014 better.
