Olive Oil Defects
Olive Oil Defects


Not all olive oil earns the grade of extra virgin. During the long journey an olive takes from the
tree to your table, the integrity of an oil can be compromised. Below is a basic list of possible
defects that can occur.


Fustiness refers to anaerobic fermentation (fermentation without oxygen) and can produce oil
with a barnyard or swamp-like smell. This often occurs when olives sit in heaps for long periods
of time prior to processing.


Rancidity refers to the breakdown of fat molecules in an olive oil. As any oil ages, it oxidizes.
The resulting flavor can smell like crayons or paint thinner. For this reason it is important to
slow down oxidation by storing oil in a cool, dry, dark place and by using it soon after it is
produced and quickly after it is opened.


Winey refers to aerobic fermentation. It can produce a sour or vinegary smell and taste in an
olive oil.


Musty refers to a moldy flavor attribute. Mustiness can occur if wet olives begin to grow mold
prior to milling.


Frozen is a flavor that occurs when olives are hit by frost prior to processing. Frozen oil can
range in flavor from developing attributes similar to mushrooms or green apples.