In Greece there are more than 32 native varieties of olive trees. Among others, the most popular and most common as they produce high quality olive oil are Manaki, Koroneiki, Athinolia and Kolovi. During the stages of maturity, olive fruit changes colour from green to violet and then black. Olive Oil taste characteristics depend on which stage of ripeness olive fruits are been collected. Olive Oil coming from green to violet olive fruits contains large amounts of phenolic and aromatic compounds and has intensive fruity and herbal taste (Koroneiki and Athinolia variety). On the other hand, as the fruit becomes riper the amounts of phenolic and aromatic compounds are getting lower. The taste of olive oil that comes from violet to black fruits is softer and its aroma reminds ripe fruits like apple, tomatoes and sometimes almonds (Manaki variety).