Profiling triacylglycerols, fatty acids and tocopherols in hazelnut varieties grown in Turkey

Profiles of triacylglycerols, fatty acids and tocopherols of fourteen Turkish hazelnut varieties harvested in the years of 2013 and 2014 were identified. Glyceryl trioleate (OOO) was found to be the most dominant triacylglycerol in hazelnut varieties that ranged between 45.1-59.6 and 39.3-60.2% in 2013 and 2014, respectively. However, 1,2-dioleoyl-3-linoleoyl-glycerol (OOL) was in higher amounts in few varieties. 1-Stearoyl-2,3-dioleoyl-glycerol (SOO) was found to contribute least to the triacylglycerol content of hazelnut varieties, while glyceryl trilinoleate (LLL) was in lesser amounts in few varieties. The percentages of fatty acids in hazelnut varieties were in the following order; oleic acid (18:1n9) > linoleic acid (18:2n6) > palmitic acid (16:0) > stearic acid (18:0) independently of the harvest years. All hazelnut varieties were found to contain α-, β-, and γ-tocopherol, but not δ-tocopherol. The contents of α-tocopherol, the most abundant form of tocopherols, ranged between 16.5 mg/100 g oil (Kan) and 36.3 mg/100 g oil (Tombul) in 2013, and between 9.56 mg/100 g oil (Sivri) and 17.3 mg/100 g oil (Kalınkara) in 2014, respectively.