Some compositional and physical characteristics of some Turkish hazelnut (Corylus avellana L.) variety fruits and their corresponding oils

Hazelnut (Corylus avellana L.) is a popular tree nut worldwide, mainly distributed along the coasts of the Black Sea region of Turkey, southern Europe (Italy, Spain, Portugal, and France), and in some areas of the US (Oregon and Washington). Turkey is the world's largest producer of hazelnuts, contributing ~74% to the total global production. In this study, compositional characteristics of eight different hazelnut varieties grown in the Black Sea Region of Turkey were investigated. The mean total lipid content of hazelnut samples was 66.34%, which the Palas and Ham varieties showed the lowest (65%) and highest (71.03%) values, respectively. Ham variety had the highest (2.44%) ash content while Sivri variety contained the lowest ash values (0.89%). The dry matter of the fruits varied between 91.00-98.80%. Eight fatty acids were identified, among which oleic acid contributed minimum 84.3% to the total, followed by linoleic, palmitic, and stearic acids. Unsaturated fatty acids accounted for 90.2% of the total fatty acids present. The ratios of polyunsaturated/ saturated and unsaturated/saturated fatty acids of hazelnuts varieties were found between 1.15 and 1.94, and 14.1 and 18.3, respectively.