Effect of the Harvest Time on Oil Yield, Fatty Acid, Tocopherol and Sterol Contents of Developing Almond and Walnut Kernels.

Oil content and bioactive properties of almond and walnut kernels were investigated in developing almond and walnut kernels at 10 days intervals. The oil contents of almond and walnuts after the first harvest (1.H) stage changed between 46.2% and 55.0% to 39.1% and 70.5%, respectively (p<0.05). Oleic acid contents of almond and walnut oils ranged from 71.98% (1.H) to 78.68% (5.H) and 10.51% (1.H) to 16.78% (2.H) depending on harvest (H) times, respectively (p<0.05). In addition, linolenic acid contents of walnut and almond oils were found between 62.35% and 67.78%, and 12.02% and 17.65%, respectively. The almond kernel oil after the first harvest stage contained 1.045, 1.058, 1.018, 0.995 and 0.819 mg/kg ɑ-tocopherol, respectively. γ-Tocopherol contents of walnut oil changed between 1.364 (3.H) and 2.954 mg/kg (1.H). The β-sitosterol contents of both almond and walnut oils were found between 1956.6 (5.H) and 2557.7 (1.H), and 1192.1 (3.H) and 4426.4 mg/kg (1.H). The study exhibited the presence of high percentage of oleic and linoleic for almond and walnut, respectively, and γ-tocopherol and β-sitosterol.