One of the negative attributes sometimes found in extra virgin olive oil is an overtly metallic taste.
Oils described as metallic have an instantly recognizable metal flavor to them. Perhaps unsurprisingly, this attribute is found in oils that spend too much time in contact with the metallic surfaces of machinery during the grinding, malaxation (the mixing of the olive paste), pressing and storage processes. In other cases, a metallic taste can be caused by storing the oil in unsuitable metal recipients.
This defect is immediately recognizable and identifiable and is mainly detected during tasting.