Everyone has experienced apples with brown spots or dents after peeling them. Is it safe to eat?

Dents, a spongy texture beneath the skin, and café-au-lait spots are all signs of bitter pit.

Actually, these aren’t rotten apples. They’re caused by a calcium deficiency during apple growth called “bitter pit,” a physiological condition associated with calcium deficiency.

Bitter pit in apples is primarily caused by calcium deficiency, as calcium strengthens plant cell wall development and reduces physiological damage to the skin cells. Therefore, when calcium deficiency occurs in localized tissues of apples, combined with poor soil conditions (e.g., excessive nitrogen and potassium fertilizers), or unstable soil moisture, the integrity of the cell walls is lost, leading to bitter pit.

Bitter pit causes physiological damage to the skin cells, resulting in slight dents and a spongy flesh. Sometimes, the spots aren’t noticeable on the surface of the skin, but appear within the flesh, usually only visible after peeling. Apples with bitter pitting aren’t rotten, and eating them doesn’t pose any health risks. They just have a bitter taste. So, if you find these coffee spots, you can still eat them without throwing away the whole apple.