فهرست نشریات علمی دسترسی آزاد ایران

The current study was conducted to characterize chemical composition of wild pistachio namely Qazwān (Pistacia atlantica subsp. kurdica) kernel, and physicochemical and functional properties of its protein as a function of pH. The chemical composition analysis indicated that Qazwān kernel is a good source of nutrients containing high amounts of protein, oil, and fiber. Sodium-dodecyl sulfate polyacrylamide gel electrophoresis revealed that molecular weight of protein extract was below 60 kDa with subunits distributed from medium- to low-molecular weight. The protein contained all essential amino acids with reasonable amounts and Osborn fractionation indicated that globulin fraction has the dominance. The protein morphology was platelet-like containing embedded spherical particles. The extracted protein showed highly ordered structure made mainly of α-helix and β-sheet elements, irrespective of the pH value. The functional attributes of protein were pH-dependent, so that the most favorable properties were observed when the pH was below isoelectric point, including solubility, water and oil holding and foaming capacity, while emulsifying activity and emulsion stability indices along with foam stability were the highest at pH values above isoelectric point. The findings suggest that Qazwān nut could be a promising nutritious source of protein exhibiting comparable functionalities to other protein sources. In this regard, this protein source can be suggested as an alternative ingredient for traditional proteins in product formulations and specialty foods.