Can you still eat a tangerine if part of it has gone bad?
Generally, whether a partially spoiled sugar tangerine can be eaten depends on the type and extent of damage, particularly signs of mold. If only minor bruising has occurred with no mold present, it is safe to eat after removing the damaged portion. However, if there are visible signs of mold, the entire sugar tangerine should not be consumed.

If the damaged area results from slight impact during transportation or storage—such as superficial skin breakage or localized softening of the flesh—and there are no mold spots or unpleasant odors, the remaining fruit tissue, provided it appears normal in color, firm in texture, and free of off-odors, is typically uncontaminated by mold. In such cases, consuming the undamaged portion is generally safe and unlikely to cause discomfort.
However, if the spoiled part shows mold, slimy flesh, or emits a sour, rotten smell, even cutting away the visibly damaged section may not make the fruit safe to eat. Mold filaments and their toxins may have already spread into areas that appear unaffected, making them difficult to detect with the naked eye. Consuming such fruit may irritate the gastrointestinal tract, leading to abdominal pain, diarrhea, or other discomforts, posing risks to health. Therefore, the entire sugar tangerine should be discarded.
For daily storage, sugar tangerines should be kept in a cool, well-ventilated place, protected from pressure and physical impact. Any fruit with minor bruises should be consumed promptly. If mold is detected, the affected fruit should be disposed of immediately to prevent contamination of other healthy tangerines.