ABSTRACT

Hazelnut (Corylus avellana L.) belongs to the Betulaceae family and is a popular tree nut worldwide, mainly distributed in the coasts of the Black Sea region of Turkey, southern Europe (Italy, Spain, Portugal, and France), and in some areas of the United States (Oregon and Washington). Hazelnut is also cultivated in some other countries such as New Zealand, China, Azerbaijan, Chile, Iran, and Georgia, among others. Turkey is the world’s largest producer of hazelnuts, contributing ∼74% to the total global production, followed by Italy (∼16%), the United States (∼4%), and Spain (∼3%). Other countries contribute ∼3% to the total production [1]. Hazelnut is, therefore, the most popular tree nut in Europe. Several commercial hazelnut varieties are available [2-10]. Although each hazelnut variety has its own nutritional composition, distinctive taste, and aroma, for example, Tombul (round) hazelnut variety, grown throughout the Giresun province of Turkey, is classi ed as Giresun quality (also known as prime quality) among 17 commercial hazelnut varieties cultivated in Turkey [11,12]. The prime quality varieties differ for each production region as Tombul for Turkey, Tonda gentille for Italy, Negret for Spain, Fertille de Coutard (also known as Barcelona) and Segorbe in Portugal, and Barcelona, Ennis, Daviana, and Butler for the United States.