231 Chemical Composition and Nutritive Value of Selected Walnuts (Juglans regia L.) from Turkey U. Ertürk 1 , T. Şisman 2 , C. Yerlikaya 3 , O. Ertürk 4 and T. Karadeniz 5 1 Department of Horticulture, Faculty of Agriculture, University of Uludag, Bursa, Turkey 2 Esenler District Directorate of Agriculture, Istanbul, Turkey 3 Chemical Engineering Department, Istanbul Technical University, Istanbul, Turkey 4 Department of Agricultural Constructions and Irrigation/Biosystems Engineering, Faculty of Agriculture, Uludag University, Bursa, Turkey 5 Department of Horticulture, Faculty of Agriculture, University of Ordu, Ordu, Turkey Keywords: Juglans regia L., walnut, proximate composition, minerals Abstract Walnut has an important part in the human diet since ancient times. In this study, seven walnut genotypes (28 ÇO 012, 28 ŞK 033, 28 ŞK 050, 28 ŞK 108, 28 ŞK 351, 28 ŞK 550, 28 ŞK 935) and the ‘Şebin’ cultivar grown in Turkey were selected and evaluated for proximate composition and mineral quantities. Concerning their composition the main constituent of kernels was oil ranging from 62.17 to 68.93%, the nutritional value being around 700 kcal per 100 g of kernels. Kernels had a range of 12.15 to 16.85% in protein content and 10.54 to 19.53% in carbohydrate content. Ash ranged from 1.68 to 2.05% while the moisture content of the kernels was found between 3.29-6.62%. Potassium was the major mineral compound in all genotypes sampled, ranging from 372.69 to 554.69 mg/100 g, followed by calcium, ranging from 112.02 to 237.08 mg/100 g and magnesium ranging from 127.08 to 155.37 mg/100 g. INTRODUCTION Walnut fruits have considerably high nutritional value. Fruits are particularly rich in terms of unsaturated fatty acids and proteins and with the mineral elements content walnut has a considerable important place for human nutrition. Depending on genotype and geographic region the content of walnut fruit shows some changes. Nevertheless, this situation is not a distinctive property between cultivars and origins. The walnut kernel (Juglans regia L.) generally contains approximately 60% oil. In addition to oil, walnuts provide appreciable amounts of proteins (12-24%), carbohydrates (12-18%), fibre (1.5-2%) and minerals (1.7-2%) (Prasad, 1994; Lavedrine et al., 2000; Savage, 2001; Amaral et al., 2003). In the studies, it was determined that walnut contains high levels of potassium (355-911 mg/100 mg) phosphor (299-434 mg/100 g) and magnesium (99-278 mg/100 g); on the other hand, considerably low levels of sodium (0.13- 6.70 mg/100 g) (Lavedrine et al., 2000; Yarılgaç et al., 2003; Özcan, 2009; Ali et al., 2010; Muradoğlu et al., 2010; Cosmulescu et al., 2009). It is well-known that Anatolia is the motherland and one of the oldest cultivation areas of walnut (Juglans regia L). Walnut is cultivated in almost every region of Anatolia. Throughout the years Anatolia has a very rich walnut population due to cultivation from seed. This study was made to determine some proximate and mineral contents of selected genotypes from Şebinkarahisar territory located in the northern Anatolia Region. MATERIALS AND METHODS Seven walnut (Juglans regia L.) genotypes: 28 ÇO 012, 28 ŞK 033, 28 ŞK 050, 28 ŞK 108, 28 ŞK 351, 28 ŞK 550, 28 ŞK 935 and the commercial cultivar ‘Şebin’ were evaluated for their proximate and mineral composition. The genotypes were selected in Şebinkarahisar district which is rich in genetic resources of walnut. The genotypes grew in a natural condition and they had only been irrigated in drought seasons and no mineral fertilization was applied. It is located at an altitude of 1350 m in the northern Anatolia region of Turkey. After harvest, walnut fruits were immediately dried and stored in the Proc. VII th International Walnut Symposium Ed.: Jianbao Tian Acta Hort. 1050, ISHS 2014