The natural question to ask at this point is: can a fruitcakes really be kept at room (or cellar) temperature for weeks, even months without spoiling? Yes, my friends, they can. Well-made fruitcakes have been known to keep for years, even decades if you can believe it. And you probably can.
One of the big reasons is that they’re so darn sugary, and as has been often discussed in this space, sugar in high enough doses is as lethal to microbes as salt. This is why some of the really old fruitcake recipes call for a thick sugar glaze to be poured over the top. It forms a nigh-impenetrable bug barrier, provided it’s kept dry (the same goes for dustings of powdered sugar…they do more than make a cake look pretty, believe me). Inside, the crumb itself is usually quite sugary, and that serves to keep microbes down. But what else might we use to keep any critters that still might be hanging on from growing out of control?
Anyone? Anyone? Yes, you in the back with the high ball. Right! Booze! For alcohol is the ne plus ultra, the sine qua non, if you will, of bug-killers. A liberal soaking, therefore, combined with periodic turning to keep it well distributed, will keep a fruitcake “pickled” almost indefinitely. Thus the old tippler’s retort to his wife’s complaint about too much liquor in the cake: What, you want me to die of botulism?
In order to take full advantage of the preservative power of liquor, it’s important that the good stuff (or more of the good stuff) be added after the cake is baked. Otherwise most of the alcohol will simply evaporate out in the oven. Spritzed-on spirits will soak in and remain if applied regularly. However there’s also the more direct approach. My old man, as previously mentioned, uses a horse needle. However a few little holes made with a skewer or toothpick accomplishes pretty much the same thing. Just dribble a few teaspoons on every few hours, for as long as you think necessary. Then turn the loaves every few days to keep the alcohol distributed.
All this begs the question why preserving a fruitcake is such a big deal to begin with. In all honesty, I can’t say I know. Back in the day of course (and we’re talking pre-industrialization) long-keeping foods were highly prized. A sweet and boozy fruitcake would have been an excellent source of nutrition for a traveler say, or just to have on-hand during a lean winter. Or maybe it’s simply that “ripe” fruitcakes just taste better than young ones. Bread bakers, vintners and cheese makers have long known that controlled microbial activity is a fabulous flavor-producer.
There are true aficionados out there who think of fruitcakes like fine wines, “laying them down” for anything up to a decade, fortifying them with a little extra liquor every so often to make up for anything that might have evaporated. That’s going too far in my opinion. But then I’ve never tried one. I may be missing out.