The humble fruitcake has stood the take a look at of time—both culturally and scientifically. A person of the earliest references to the dessert dates to the Historic Romans, who utilised it like an vitality bar and filled it with pomegranate seeds, raisins, honey and wine. Soldiers in Globe War I also fancied a version of the baked take care of: wrapped in wax paper, this smaller fruitcake presented some morsel of nutrients when lots of other meals would spoil during long stretches in barren battle trenches.

Presently fruitcakes are a holiday getaway delicacy still prized for their very long-lasting freshness. In accordance to the U.S. Division of Agriculture, these seemingly indestructible pastries typically continue to be clean for six months in the pantry and up to a calendar year when refrigerated. But anecdotally we know that they can final for many years some of the oldest have been preserved for much more than a century. In 2017 a then 106-calendar year-previous fruitcake remaining at the rear of by associates of a 1910 Antarctic expedition was unearthed from a person of the continent’s initial buildings. And in 2019 the Detroit Information reported that a Michigan household treasured a then 141-yr-previous fruitcake as an heirloom. And you could theoretically nonetheless consume these century-previous cakes without harm—if you can get earlier the nauseating, rancid scent.

The solution at the rear of the long shelf lifestyle of the beloved (or often despised) holiday take care of lies in the elements and preparing. Scientific American spoke to foodstuff experts about what can make an edible merchandise seemingly indestructible and irrespective of whether it is a great plan to consume a fruitcake that has been saved up for a long time.

Sugar and liquor produce a hostile atmosphere for microorganisms

1 ingredient that bolsters fruitcake’s longevity is alcoholic beverages, states Bryan Quoc Le, a food items scientist and school investigate fellow at Pacific Lutheran University. Several traditional property recipes involve soaking the cake in rum, brandy or bourbon—liquor that can add some taste but is typically used for its antimicrobial qualities. Alcohol would make a fruitcake much more acidic, building a harsh ecosystem for many typical foodborne microbes. Booze destroys the cells of a lot of germs, mould spores and other prospective pathogens that endure the baking process or accumulate when foods is left out at room temperature.

But even however alcoholic beverages is frequent in common do-it-yourself recipes, commercially geared up fruitcakes rarely incorporate it, notes Benjamin Chapman, head of the agricultural and human sciences office at North Carolina Point out College. The shelf lifestyle of an liquor-no cost fruitcake is likely shorter than one ready with spirits.

The fruit in a fruitcake is often dried rather of refreshing, which reduces humidity and produces this dessert’s notoriously dry texture. This, alongside with the superior sugar information, sucks up much of the h2o that microorganisms need to have to survive. “Foods with small quantities of moisture, like fruitcakes and Twinkies, are resistant to the advancement of microorganisms since you will need a selected quantity of moisture for spoilage and pathogenic microorganisms to increase,” Le explains. “If you can get rid of the moisture, you have a little something that is just about indestructible.” The deficiency of h2o is one rationale why one particular unwrapped Twinkie dessert has lasted for at minimum 43 yrs even with having experienced a shelf existence of just times when it was generated. Chapman also says commercially organized fruitcakes and Twinkies have antibacterial and antifungal preservatives to raise their shelf everyday living.

A fruit cake’s dense texture stalls staleness

Fruitcakes have a popularity for remaining as hefty as a rock. But it’s partly many thanks to this substantial density that they remain refreshing for a longer time than breads and cakes with light-weight, fluffy textures, Le claims.

The interplay concerning density and humidity influences how quickly foods grow to be stale. When bread is baked, drinking water in the dough rearranges starch molecules from a rigid framework to a disorganized just one that helps to sort air pockets. Baked goods built with wetter dough have additional air pockets, which build a smooth, light-weight texture. But the porousness also exposes extra starches to the exterior air, which attracts out h2o and eventually shuffles the starch molecules back again into a solid crystalline structure. The resulting rigidity can make the moment-supple baked merchandise stale and challenging to chew. Fruitcake’s denser texture lets far fewer air pockets to type, protecting much more of the starches from the air.

Could you stomach a 50-calendar year-aged fruitcake?

Like a wonderful wine, a very well-produced fruitcake can truly get a lot more flavorful more than time. Tannins ooze out of the dried fruit, chemically changing the cake’s composition to make a fruity and spicy taste. Some bakers endorse intentionally aging fruitcakes for a number of months to months in a interesting, darkish location to boost the taste and texture. But these enjoyable, elaborate flavors only past about a yr or two, Le states. This is because of oxidation, a procedure whereby chemical reactions among the food and oxygen change unsaturated fatty acids into compounds termed lipid hydroperoxides. Even more breakdown of these compounds makes smaller molecules this sort of as aldehydes and ketones, which can generate bitter or unpleasantly leatherlike flavors and aromas. “The probability that any of the fats in a [50-year-old] fruitcake are not oxidized or rancid is pretty very low,” Chapman provides.

That said, even even though a many years-old fruitcake may flavor like a leather-based shoe, ingesting it most likely will not make you dangerously unwell. Chapman states the dessert’s attribute resistance to pathogen advancement drastically cuts down the risk of foodborne diseases from Escherichia coli or Salmonella bacteria—though men and women may turn into nauseous from the smell and flavor. While the 50-calendar year-aged dessert would almost certainly taste pretty awful, he provides, “the fruitcake is no fewer safe now than the yr it was baked.”

Despite fruitcake’s perfectly-preserved standing, it is not normally the most well-known item on the vacation dinner desk. The dessert has gained a reputation for staying the reward no 1 likes to get—but it can be the gift that retains providing. If you acquire one particular this Christmas, know that you have subsequent calendar year (and every 12 months after) to discreetly regift it.