Many small olive producers have already finished their olive harvest and the big producers should be a few weeks away from completing theirs. After a very low yielding harvest last year, the producers are pleased to see a much better harvest in 2015, although certainly nowhere near a record harvest.
The olive harvest starts after the grape harvest, which is convenient for those farms that produce both! The season is about two months long. Olives are picked by hand for table olives and raked into collecting sheets on the ground for olive oil. The cost of labour is one of the main contributors to the price of olive oil.
Some of the largest producers have harvesting machines which either shake or rake the trees. Without them they would not be able to harvest from all the trees fast enough to ensure optimal ripeness of the olives.
As with grapes, the olives must be processed the day they are picked. If they are not, they could start to oxidise and that will affect the quality of the whole batch of olive oil. Olives are harvested at differing ripeness in order to get a balanced oil. Some are harvested when they are still green, others when they are fully ripe (black), and some are harvested when they are half green, half black.
Different varieties ripen at different times so large producers would select varieties that ripen over the season in order to ensure they are able to harvest them all in time. Some producers harvest 24 hours a day to get the olives at optimal ripeness!
Smaller producers will collect different varieties together and press them together, creating an oil that is a product of their plantings and terroir. Larger producers will press and store each variety of olive separately and once all the olives have been pressed, they will then create a specific blend from the different varieties. That blend will fit a flavour profile that remains consistent from year to year, just like some popular wine blends.
The oil will be stored in tanks with an inert gas on top to protect it from oxygen. Batches will be blended as demand dictates. Each blended batch is sent for chemical analysis to ensure that it qualifies as extra virgin and then sent to the SA Olive Association to be tested by a tasting panel to verify that it is fault free. That oil can then be sold with the Commitment to Compliance sticker of the SA Olive Association. This sticker indicates the year of harvest and that the contents of the bottle/box have been verified as extra virgin.
Most olive oils on the shelf should have this sticker and the consumer can use it as a way of ensuring the product they purchase is what it says it is: extra virgin olive oil from that specific year of harvest. Always try and purchase from the most recent harvest as olive oil is best when freshest. The 2015 oils are just starting to hit the shelves, so look out for them.