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The cooling of olives stored in containers with a capacity of 400 kg risk accumulation of respiration heat and subsequent fruit deterioration. Pre-cooling the fruit to 5 °C before cold storage was studied as a possible solution to overcome this obstacle. The fruit temperature within the containers was recorded daily for 14 days and oil was extracted at days 0, 4, 8, and 14. A second experiment evaluated a rapid pre-cooling procedure at -18 °C for 3 min. No significant alterations at the level of the examined parameters were recorded. The internal temperature of the control container declined and stabilized at around 12 °C. The temperature of the pre-cooled fruit increased to up to 8 °C. The examined parameters showed no significant alterations in either experiment and the rapid pre-cooling treatment did not lead to any visible ‘chill injuries’. A pre-cooling treatment at 5 °C was successfully introduced at the farm of a small producer.

Currently, hand harvesting is the most widely used method to harvest table olives. However, table olives profitability is in a delicate situation due to low prices and steady rising costs. Economical feasible mechanical harvesting methods are in development in some producer countries such as USA, Spain and Israel, in order to improve this sector competitiveness. This research aims to improve mechanical harvesting performance in existing orchards. Results show that the mean value of harvester efficiency with trunk shakers is 72 %, without additional rod beating or abscission agents are not applied. In orchards where the trees have been trained into shapes that facilitate the vibration transmission, fruit properties have had a limited effect on harvester efficiency. In order to achieve harvester efficiency greater than 85 %, the tree trunk vibration parameters were set above acceleration value of 183 m s-2, and at a frequency of 28.1 Hz. Adjusting the vibration parameters, giving an adequate power of the machine, training the canopy to reduce volume thus facilitating the vibration transmission to the fruit, together with effective reduction of fruit bruising and mitigation of bark damage are all required to ensure the success of vibration harvesting systems for green olive processing.