Effect of gamma-irradiation on physico-chemical and functional properties of arrowhead (Sagittaria sagittifolia L.) tuber flour

Flour prepared from wild arrowhead tubers was treated by gamma-irradiation at 0, 5, 10 and 15 kGy doses. Chemical composition of native flour revealed moisture, protein, fat and ash contents were 8.55 g/100 g, 5.62 g/100 g, 6.01 g/100 g and 3.91 g/100 g, respectively. Physicochemical, pasting and functional properties of native and irradiated tuber flours were investigated. Physicochemical properties of unirradiated flours differed significantly (p≤0.05) from irradiated flours and showed strong dose dependent relationship. Solubility and transmittance increased whereas swelling power, bulk density and syneresis decreased upon irradiation. Pasting properties like peak, trough, final, and setback viscosities were significantly reduced, whereas the breakdown viscosity increased following irradiation. Functional properties including water absorption capacity, foaming and emulsification properties increased significantly at 10 kGy and higher dosage.