Chemical Composition and Physicochemical Properties of Pumpkin Seeds (Cucurbita pepo Subsp. pepo Var. Styriaka) Grown in Iran

Chemical composition and physicochemical properties of pumpkin seeds and fatty acids of their oil were determined. It was found that the seeds contained 41.59% oil and 25.4% protein. Moisture, crude fiber, total ash, and carbohydrate contents were 5.2%, 5.34%, 2.49%, and 25.19%, respectively. The specific gravity, dynamic viscosity, and refractive index of the extracted pumpkin seed oil were 0.915, 93.659 cP, and 1.4662, respectively. Acid value (mg KOH/g oil), peroxide value (meq O2/kg oil), iodine value (g I2/100 g oil), saponification number (mg KOH/ g oil), and unsaponifiable matter content (%) of the extracted oil from pumpkin seeds were 0.78, 0.39, 10.85, 104.36, 190.69, and 5.73, respectively. Total phenolics compounds (mg gallic acid/kg oil), total tocopherols (mg α-tocopherol/kg oil), total sterols (%), and waxes (%) were 66.27, 882.65, 1.86, and 1.58, respectively. Specific extinctions at two wavelengths of 232 nm (K232) and 270 nm (K270) and R-value (K232/K270) were 3.80, 3.52 and 0.74, respectively. Gas chromatographic analysis of the pumpkin seed oil showed that the linoleic (39.84%), oleic (38.42%), palmitic (10.68%) and stearic (8.67%) acids were the major fatty acids. Compared with other vegetable oils, the present study revealed that pumpkin seed oil can be a valuable source of edible oil.