Physical and chemical composition of pistachio nut outer shell oils

The scope of this research, in order to determine the physical and chemical properties of Red and Long pistachio shell oils were performed in the outer shells; dry matter, ash and oil analysis and outer shell oils; free fatty acidity, peroxide number, color, iodine number, viscosity, specific gravity, saponification number, unsaponifiable matter number, refractive index, tocopherol analysis, fatty acid composition, sterol composition and mineral substance analyzes. In this direction, the dry matter, ash and oil amounts of Red and Long pistachio shells were determined as 9.29 - 8.69%, 7.60 - 8.17%, 11.60 - 9.30%, respectively. On the other hand, the results of free fatty acidity, peroxide number, iodine number, viscosity, specific gravity, saponification and unsaponifiable matter number, refractive index and tocopherol content of Red and Long pistachio shell oils were found 3.37 – 5.90%, 9.00 – 8.00 meqO2/kg, 91.17 – 57.88 g I2/100g, 158.0 – 253.0 mPa, 0.965 – 0.982 g/cm3, 113.97 – 102.77 mg KOH/g , 9.77 – 7.37 g/100g, 1.5014 – 1.5087, 112.80 – 99.75 mg/100g respectively. When the fatty acid composition of Red and Long pistachio shell oils was examined, palmitic, linoleic and arachidic fatty acids were determined as dominant fatty acids. In terms of sterol composition, β-sitosterol, campesterol, ∆7-stigmasterol and stigmasterol sterols were determined, among which both types of shell oils were found to be rich in β-sitosterol. In terms of mineral matter, B, Mg, Al, Ca, Mn, Fe, Cu, Zn, Rb and Cs mineral substances were detected in the Red and Long shell oils. As a result; Pistachio outer shell oils obtained from different varieties which are waste after processing pistachios and are not used should be used externally due to the high free fatty acidity and peroxide number values. In addition, it is recommended to investigate pharmacological and toxicological aspects in future studies.