Olive Oil Defects: The Official Taxonomy of Failure

The International Olive Council (IOC) doesn't just certify what good olive oil smells like. It keeps an official list of olive oil defects too, and it's oddly specific. Fusty, musty, muddy sediment, and winey-vinegary aren't casual insults. They're certified categories, each with its own cause and its own name.

Fusty: olives piled up too long before milling, fermenting anaerobically like a gym bag left in a locker.

Musty: mold, plain and simple, from olives stored damp.

Muddy sediment: oil left sitting against the wet residue at the bottom of a tank too long. It is fusty's close cousin, different route there.

Winey-vinegary: fermentation that went past fruit and turned into something closer to vinegar.

Every one of these four olive oil defects is official, certified, and taken seriously enough to disqualify a batch from calling itself extra virgin. This tells you exactly how seriously this industry takes the business of smelling things.
That seriousness is trained, not innate. Certified olive oil tasters, if you borrow a word from wine world- EVOO Sommeliers, calibrate their palates against standardized reference kits, vials of oil deliberately spiked to replicate each defect at controlled intensity.

A “fusty” call in Jaén means exactly the same thing as a “fusty” call in Crete. Panel testers re-qualify periodically, the same way a lab instrument gets recalibrated. Taste, treated as an instrument. Fusty. Musty. Muddy sediment. Winey-vinegary. Four different olive oil defects, four different causes, one shared outcome: the oil is not extra virgin anymore.

None of these show up anywhere in KORAJE sensory panel results. Our fruitiness scored a 7. That's the entire point of picking fast and milling faster.

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