how does aged eggnog not spoil

We all have those moments when, in search of that jar of pickles or maybe the curry paste, we unearth a container, deep in the back of our fridge, that was probably best left unearthed. Stratified, congealed, cloudy, and impossible to identify as what it once was. Those are the times when you skip the sniff test and throw the entire sealed container into the trash.

Or, if youre like me, you give it a little pat; say to yourself, Its not quite ready yet; and gently place it back in its corner, where it belongs.

You see, for the last year, Ive had two quarts of my eggnog hanging out in the back corner of my fridge, waiting to be cracked open and tasted. That time has finally come.

I first heard about aged eggnog when Michael Ruhlman wrote about it on his blog back in 2008, but it didnt seem to become wildly popular until last year, when folks started recommending making your eggnog up to a year in advance, claiming that mellower, more complex flavor and richness would be the rewards youd reap. Think of it as your past self leaving a little holiday gift for your future self, and the nice part is, your future self doesnt even have to send a thank-you card.

But heres the real question: Is aged eggnog all its cracked up to be? Is it worth giving up fridge space for a year? Is it even better at all? I mean, I like cool things and fun experiments, but there has to be a reason to age eggnog beyond just the “its cool!” factor, right?

The reason eggnog can age despite its dairy content is twofold. One half is that contamination of American dairy products is, thankfully, quite rare. The other is that alcohol inhibits bacterial growth. In pre-pandemic times, you may have joked that “alcohol kills everything” while sharing cocktails in a crowded bar.

The Tasting

For my taste test, I set up a simple blind triangle test, in which I served nog in containers marked A, B, and C. In this case, container A held nog that had been aged for a year, while B and C both contained fresh nog. I vigorously shook each container to homogenize and froth the contents before serving, and I asked the tasters to taste all three before commenting. Tasters also tried them in random order (i.e., not everyone started with batch A). Right off the bat, it was abundantly clear that A was the outlier. Aging for a year makes a huge difference in flavor, and no tasters were confused by that. But was it a positive difference? Given all the hype for aged nog, I assumed it would be, but I was surprised to find that the exact opposite was the case. Tasters unanimously preferred the fresh stuff over the aged.

While fresh eggnog is simple, smooth, and, well, fresh-tasting, aged eggnog is much more aggressive. The booze comes out stronger, and there are medicinal, almost minty flavors that people will pick up on—almost as if youve spiked your eggnog with an herbal liqueur, like Fernet-Branca. Those flavors on their own are not bad. I quite enjoyed them, actually, but when coupled with the sharpness of the booze, they become overbearing.

I was a little surprised. The results of my taste test were in direct opposition to one conducted by the generally reliable Cooks Illustrated. They found, unanimously, that aged nog was mellower and smoother than fresh nog. Similarly, Alton Brown says that “the longer the nog ages, the more mellow it will get.” In The Art of Eating, Holly Jennings found three-week nog to be “rounder, smoother, and noticeably more complex.”

But then there are some outlying voices that agree with my findings. Boozenerds.com found that nog peaked at three weeks, then went downhill from there (the oldest they tasted was five weeks old, and it was described as “eggy” and “almost metallic”), while Julia Thiel of the Chicago Reader claimed that year-old nog had “more depth and complexity of flavor,” but that “the booziness made it a little difficult to drink.”

Thiels assessment is most in agreement with my own. The nog was definitely more complex—new flavors had developed that are not present in fresh nog—but the booziness came strongly to the forefront.

So what accounts for the different results? The main thing seems to be age. All of the side-by-side blind taste tests Ive seen have pitted nogs aged for just a few weeks against fresh nog. Those that claim that nog gets mellower continuously over time dont offer experimental data to back up those claims, and we all know how easily the human mind can trick itself without the benefit of blind tasting.*

*This all reminds me of a taste test I performed on aged whiskey, in which tasters who thought they were drinking older whiskeys ranked them better, even if the whiskeys were in fact younger or identical.

Cooks Illustrated also conducted its test quite differently, omitting the dairy from the aged nog and adding it just before serving, which could further skew the results. To be fair, my taste test also had a small sample size, only five tasters.

If I had planned better, I would have made batches of eggnog month to month throughout the whole year, week to week for the last two months, and day to day for the last two weeks. so that I could do a full blind taste test tracking changes over time. Unfortunately, I didnt, and itll take me another full year if I want to try this out again. Such is the pace of good science.

But! Heres my request to all of you: Go out and make a batch of my eggnog sometime in the next couple of months (make sure to note the date!), save it in your fridge for the holidays, make up a fresh batch, then have your friends and family taste the two side by side (blind, of course!). Ill set up some kind of forum for us all to report back, and well see where that data takes us.

Safety

You must be wondering: Is it safe? Statistically, about one in every 20,000 eggs sold in the US is contaminated with salmonella, so, assuming youre getting a random sample of eggs and using eight of them in a batch of nog, thats a .04% chance of being exposed. But eggnog contains booze, and booze kills bugs. How well? Very well.

A team of microbiologists at Rockefeller University, in what sounds like a late-night-at-the-holiday-party-inspired bit of good science, proved that, at least in lab conditions, given an alcohol content of 20%, eggnog comes out the other end completely sterile after just 24 hours of resting. Thats cleaner than eggnog bought in sealed cartons from the supermarket.

Short answer: Yes, its safe. At least, its as safe as anything with a 20% booze content can be.

Aged Eggnog: Is it worth the wait? (Results may surprise you!) – Through the Mixing Glass

FAQ

How is aged eggnog safe?

Why does eggnog get better with age?

Why does egg nog not spoil?

How does eggnog last so long?

Is aged eggnog safe?

Once you taste homemade aged eggnog, you’ll never go back to store-bought again. Its healthy, rich, creamy texture and depth of flavor are unbeatable. Making aged eggnog is one of those holiday traditions we enjoy sharing with our adult family members and friends. I have been making batches of eggnog for years, safely and with great success.

How long can raw eggs last in the refrigerator?

It can last from 4 to 5 weeks depending on the state of your refrigerator. Please make sure to check whether there are broken eggs before storing them in fridge. Remove broken eggs to prevent contamination with the other eggs.

Does eggnog come out sterile after 24 hours?

Very well. A team of microbiologists at Rockefeller University, in what sounds like a late-night-at-the-holiday-party-inspired bit of good science, proved that, at least in lab conditions, given an alcohol content of 20%, eggnog comes out the other end completely sterile after just 24 hours of resting.

Can you make aged eggnog ahead of time?

It seems the holiday season always creeps up on us, and preparing ahead of time is key. With many traditions around home cooking and holiday drinks, aged eggnog is definitely on the menu. The art of homemade aged eggnog dates back long ago, but Alton Brown has made it a popular cocktail recipe once again.