With the polar vortex having recently swept over the United States, people have been seeing some interesting phenomena, like frozen surfers and now even mysterious frozen apples. Such apples were recently discovered in western Michigan by a farmer named Andrew Sietsema, who nicknamed them ‘ghost apples’.
In an interview with Bored Panda, the farmer said he shakes the trees when pruning them and the mush slips out of the bottom of the ‘ghost apples’. “Most apples just fell off, ice and all. But quite a few would leave a cool ‘ghost apple’ behind,” said Andrew.
“I guess it was just cold enough that the ice covering the apple hadn’t melted yet, but it was warm enough that the apple inside turned to complete mush (apples have a lower freezing point than water).”
“I’m sure you could find them at any orchard on the Ridge (near Sparta, MI), or at least any that still had a few unpicked apples hanging on the trees,” added Andrew. He says ‘Jonagold’ is one of his favorite apple varieties and he calls these frozen ones “Jonaghosts”.
Turns out not every fruit is able to form this rare phenomenon. “You could only find them on other fruits and vegetables if they remained unharvested and persisted into the winter. Most crops do not,” said the farmer.
“Besides being somewhat mummified, they could also be rotten,” described the apples William Shoemaker, a retired fruit and vegetable horticulturist from the University of Illinois. “[If so,] they maintain their form, but their substance gets closer to applesauce.”
Shoemaker said the apples did not freeze in the 18°C (0°F) temperatures because of their acidic content that has to reach extremely cold temperatures to fully freeze.