The effects of different harvest maturity and methods on fruit and oil quality of olive (Olea europea L. cv. Ayvalık Yağlık)

Abstract

Objective: This study was conducted to determine the effects of harvest time and method on fruit and oil characteristics of ‘Ayvalık Yağlık’, a major olive cultivar in Turkey. 
 Material and Methods: Early, optimum and late harvests were made by hitting with a wood stick (control), pneumatic beater, and branch shaker in a conventional olive grove located in Edremit district of Balıkesir province in western Turkey. Harvested olive fruits were stored at 18-20°C for 3 days, and physical, biochemical attributes, free acidity, and fatty acid composition, and mechanical damage caused by tested harvest methods were evaluated. 
 Results: Mechanical damage index and free fatty acidity were lower in olive fruits harvested by branch shakers compared to those dropped down by stick. Fruit weight, maturity index, oil content and linoleic acid content increased with the progress of harvest date, while color, moisture content, free fatty acids, total phenolics, and palmitic, stearic, and linolenic acid ratio decreased at the last harvest date. 
 Conclusion: The results showed that significant changes in some physical and chemical properties of the olive fruit occur with the progression of maturity, and using branch shakers and harvesting on the 2nd and 3rd harvest dates are recommended for Ayvalık variety under the experimental site conditions.