Nutritional Quality, Functional Properties, Bioactivity, and Microstructure of Defatted Pistachio Kernel Flour

摘要

Defatted pistachio kernel flour (DPKF) is a byproduct of specialty oil industries and a promising product to be further used as a food ingredient. The purpose of this study was to evaluate nutritional value, functional properties, bioactivity, and microstructure of DPKF prepared by cold pressing (partially defatted, similar to 22 % residue fat d.b.) and pre-press-solvent extraction (totally defatted, 1 % residue fat d.b.) methods both using raw and roasted kernels. DPKF was rich in protein (34.36-46.47/100 g flour, d.b.) and carbohydrate (36.61-48.71/100 g flour, d.b.). Also, DPKF showed low Na contents with high concentrations of K, P, Ca, Mg, Zn, and Se. Excluding the sulfur amino acid, all essential amino acids were significantly higher than the reference values recommended by Food and Agriculture Organization/WHO. Totally defatted flours presented better functional properties than the partially defatted ones with exceptions of foaming stability. DPKF also exhibited appreciably higher total phenolic (552-792 mg gallic acid equivalent/100 g flour, d.b.) and flavonoid (124-280 mg RE/100 g flour, d.b.) contents as well as antioxidant capacities. Therefore, DPKF may have potential applications as functional ingredients and supplements in foods.