into contact with vulnerable polyunsaturated
fatty acids in the green chloroplasts. (Leaves
are sometimes included in the grinding to
supply more chloroplasts.) The oil itself is
predominantly monounsaturated (oleic acid)
and less vulnerable to oxidation.
The Quality of Olive Oil Olive oil quality is
judged by its overall flavor and by its content
of “free fatty acids,” or fatty carbon chains
that should be bound up in intact oil
molecules but instead are floating free, and
that are evidence that the oil is damaged and
unstable. Under the regulations of the
European Economic Community, “extra
virgin” olive oil must contain less than0.8%
free fatty acids, “virgin” oil less than 2%. (To
date, quality labeling of U.S. oils is not
regulated.) Oils with higher free fatty acid
levels are usually processed to remove nearly
all impurities from the remaining intact oil
molecules — including desirable flavor