Pomegranate can develop serious internal mold while the rind looks only mildly abnormal. UC Davis describes heart rot, linked to fungi including Alternaria and Aspergillus, as a condition in which the arils become blackened inside the fruit. Because infection can develop while the pomegranate is still on the tree, the outer skin may not show a large rotten patch. If you cut a fruit open and find black moldy masses, fuzzy growth, musty odor, or extensive brown wet decay, discard the whole pomegranate.
The rind is protective, but it does not reveal every internal infection
Pomegranate skin is thick and leathery, and internal chambers are enclosed by membranes. That architecture helps protect the arils from ordinary handling, but it also means early disease can be hidden. A fruit can feel reasonably firm and show only a subtle color difference while decay advances around the arils.
The crown or calyx is one route of infection for gray mold. UC Davis notes that Botrytis can colonize blossom tissues and later grow into the rind. Heart rot follows a different pattern and may produce a mass of blackened arils. Neither problem can be ruled out simply because the outside is not visibly fuzzy.
Internal mold looks different from harmless color variation
Healthy arils range from nearly clear to pink, ruby, or deep red depending on cultivar. White membranes can tan or brown with age or chilling. Mold is more suspicious when you see fuzzy filaments, powdery growth, gray or black colonies, or arils that have collapsed into a dark mass. A musty smell is another strong clue.
Do not confuse pigment variation with decay, but do not overthink an obviously moldy interior either. Once fuzzy growth or black rot occupies an internal chamber, the amount of fruit that could theoretically be salvaged is less important than the uncertainty about spread through adjacent moist tissue.
Why cutting away the visibly moldy chamber is not a good plan
Pomegranate membranes create compartments, but fungal growth can extend beyond the obvious colony. Spores and damaged juice can also contact nearby arils as the fruit is opened. USDA mold guidance is conservative with soft, high-moisture produce because contamination can penetrate below the visible surface.
For that reason, a pomegranate with clear internal mold should be discarded rather than rinsed, sorted seed by seed, or juiced. Juicing is especially poor as a rescue method because it blends suspect material into the entire batch and removes your ability to inspect individual arils.
Inspect suspicious fruit before serving it to others
If the rind has a soft sunken area, unusual discoloration near the crown, cracking with dampness, or a musty odor, cut the fruit open before placing arils in a salad or dessert. Store sound whole pomegranates cool and dry according to normal produce guidance, and refrigerate removed arils promptly.
Internal mold is one of the cases where the absence of an obvious external warning does not guarantee a sound interior. Normal arils should be firm, juicy, and fresh-smelling. Blackened masses, fuzz, mustiness, and broad wet decay are sufficient reasons to discard the pomegranate even if most of the rind still looks good.
External clues can be subtle but still worth noticing: a crown that is unusually soft, a rind area that feels leathery and sunken, or a faint musty smell around a crack deserves inspection before the fruit is served. Do not press so hard that you damage a sound pomegranate while checking it. If several fruits from the same package show hidden black rot, retain the package information and consider reporting the lot to the retailer.
Washing the outside before cutting is still worthwhile because it reduces the chance of carrying surface dirt inward with the knife. It cannot prevent or remove heart rot that is already inside the fruit, however. If hidden decay is found, wash the knife, board, and hands before preparing other produce so moldy juice and spores are not spread around the kitchen.
Sources
- UC Davis Postharvest Research and Extension Center — Pomegranate — Heart rot, gray mold, chilling injury and internal pomegranate disorders.
- USDA FSIS — Molds on Food: Are They Dangerous? — Guidance on mold penetration in high-moisture foods.