Journal of Applied Botany and Food Quality 87, 104 - 107 (2014), DOI:10.5073/JABFQ.2014.087.016 1 Department of Horticultural Science, Faculty of Agricultural Sciences, University of Guilan, Rasht, Iran 2 Hazelnut Research Station, Astara Agricultural and Natural Resources Research Center, Guilan, Iran Evaluation of fatty acid content and nutritional properties of selected native and imported hazelnut (Corylus avellana L.) varieties grown in Iran Fatemeh Rezaei 1 , Davood Bakhshi 1 *, Reza Fotouhi Ghazvini 1 , Davood Javadi Majd 2 , Mohammadreza Pourghayoumi 1 (Received March 5, 2013) * Corresponding author Summary Hazelnut (Corylus avellana L.) is one of the most important nuts rich in valuable nutrients. In this study, chemical composition of two Iranian native varieties namely ‘Pashmineh’ and ‘Garche’ and four imported varieties, ‘Ghafghaze’, ‘Zakatala’, ‘Ronde dupimont’ and ‘Fertile decotard’ were investigated. The main fatty acid in hazel- nut varieties were oleic (71.02 %) and linoleic acid (14.45 %). The hazelnut varieties showed oil content in a range from 53.36 % to 63.5 %; protein, 16.03-23.26 %; energy, 653.4-707.65 %; ash, 2.46- 3.5 %; carbohydrate, 13.16-20.14 %; total phenolic content, 6.4- 16.42 mg GAE/g; antioxidant capacity, 57.17-72.38 %; oleic acid, 64.17-81.34 %; Linoleic acid, 10-21.07 %; Linolenic acid, 0-2 %; myristic acid, 0-0.5 %; stearic acid, 0-7.8 %; eicosenoic acid, 0- 1.69 %; palmitic acid, 0.49-9.61 %; palmitoleic acid, 0-1.6 % and behenic acid, 0-0.25 %. Introduction Hazelnut is a popular nut worldwide. It is 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 United States (Oregon and Washington). Hazelnut is also grown in New Zealand, China, Azerbaijan, Chile, Georgia and Iran. Turkey is the world’s largest producer of hazelnut, contributing around 70.3 % to the total global production, followed by Italy (11.9 %), USA (4.5 %), Azerbaijan (4.2 %), Georgia (3.8 %) and Spain (2.5 %). Other countries contribute only 2.8 % to the total global produc- tion (ALASALVAR et al., 2010). Hazelnuts, due to their organoleptic characteristics constitute, are one of the most important raw materi- als for the pastry and chocolate industry. Hazelnut also add lavor and texture to bakery, confectionery, cereal, salad, entrée, sauce dairy, and dessert formulation (ALASALVAR et al., 2003; KALEOĞLU et al., 2004; OLIVEIRA et al., 2008; OZDEMIR and AKINCI, 2004). In addition, hazelnuts play a major role in human nutrition and health, because of their special composition of fat, protein, carbohydrate, vitamins, minerals and nutrients antioxidant. (ALASALVAR et al., 2009; GARCIA et al., 1994; KÖKSAL et al., 2006; OLIVEIRA et al., 2008). At the present, nutritional interest in the fatty acid compo- sition of vegetable oils is increasing because the most important neutral lipid in most vegetable oils included in the human diet in- luences total fat and cholesterol absorption in the human lumen (ERENER et al., 2007). Monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) as well as minor lipid compo- nents play an important role in human nutrition. Also, health diets rich in MUFA, such as hazelnut oil and olive oil, decrease blood pressure and total blood cholesterol levels in human (KARABULUT et al., 2005). Every food plant contains numerous types of natural antioxidants with different properties. The actions of antioxidants have been attributed to their ability to scavenge free radicals, there- by reducing oxidative damage of cellular biomolecules such as lipids, proteins and DNA. The study of nut and kernel characteristic and nut composition helps to understand and deine the relationship between internal quality and genotype, environmental and cultural factors. It provides information for culture evaluation and choice and a reference of varietal quality useful to growers, breeders and the food processing industry (CRISTOFORI et al., 2008). Nut and kernel size, nut and kernel shape, percent kernel, shell thickness, low kernel defect, protein and high content of fatty acids are among the main characteristics considered in the evaluation of nut and kernel quality in hazelnut (BALTA et al., 2006). Studies have indicated that the nutritional and chemical composition of hazelnut is affected by cultivar, ecology, harvest year, soil, irrigation and method of cultivation (AÇKURT et al., 1999; ALASALVAR et al., 2009; BALTA et al., 2006; CAGLARIRMAK and BATKAN, 2005; CRISTOFORI et al., 2008; KÖKSAL et al., 2006; OLIVEIRA et al., 2008; SILVA et al., 2007). Recently, some studies on qualitative indices such as total phenol content, antioxidant capacity, fatty acid composition of kernel were conducted (AYDIN, 2002; BOTTA, 1997; CONTINI et al., 2008; MAGUIRE et al., 2004; OZDEMIR and AKINCI, 2004; ÖZDEMIR et al., 2001; PARCERISA et al., 1993; SERDAR and DEMIR, 2005). Unfortunately, up to date, data of fatty acid contents and nutritional properties of hazelnuts grown in Iran are scarce. Hence, the objective of this study is to determine the chemical composition of different hazelnut varieties growing in Iran. Martials and methods Plant material and growth conditions The nuts of two native variety named ‘Pashmineh’ and ‘Garche’ and four imported hazelnut varieties including ‘Ghafghaz’, ‘Zakatala’, ‘Ronde dupimont’ and ‘Fertile decotard’ were used in this study. Samples of each variety were obtained from the Hazelnut Research Institute in Astara (altitude, 22 m; latitude, 38°4 N’; longitude, 48°87 E’) located in Western-Guilan province of Iran during the 2010 harvest season. Foreign hazelnuts were provided from Horticultural and Agricultural Experiments Station, Sochi, located in Russia. Shrubs were established with shrub training system at the spacing 4×4 meter. Harvest was performed during the early August. Pollinizer was ‘Daviana’. Chemical analysis Protein, ash, total oil, carbohydrate and energy Evaluation of total oil, protein and ash contents were carried out in triplicate according to AOAC Oficial Methods (AOAC, 1995). Total oil was determined by oil extraction from ive grams of dried weight of sample using diethyl ether by a Soxhlet apparatus (CRISTOFORI et al., 2008; KÖKSAL et al., 2006; SILVA et al., 2007). Protein was determined by the micro Kjeldahl method. Protein content was calculated as total N × 6.25 (KÖKSAL et al., 2006). Ash content was determined by incineration at 600 °C (BALTA et al., 2006; KÖKSAL et al., 2006). Carbohydrate content was quantiied by calculation of the difference between total weight and other compo- nents using the following formula: Carbohydrate content = 100 % - (% moisture + % protein + % fat + % ash). (1)