Nutritional, functional, phytochemical and structural characterization of gluten-free flours

Different gluten-free flours from various sources may vary in composition and properties, thereby affecting applications in food systems. Various gluten-free flours viz. sorghum, rice, moong, water chestnut flour (WCF) and unripe banana flour (UBF) were studied in comparison with wheat flour. These were studied for their proximate composition, pH, iodine affinity value, leaching, functional properties, phytochemical analysis, color analysis, and X-ray diffraction analysis. Protein content in these flours ranged from 5.31 to 24.07%moong flour having highest protein content. Variations were observed with fat percentage from 1.01 to 3.45%. All flours were high in carbohydrate content i.e. ranged between 61.63 to 81.19%. pH values indicated slight acidic nature of all flours. UBF was found to have maximum iodine affinity value (46086 ppm). Leaching study indicated the extent of leaching with respect to time in these flours. Light transmittance was decreased with the duration of cooking for all flours. Color analysis values showed the difference in the L*, a, b values. X-ray diffractograms revealed the crystallinity patterns of the flours with percentage crystallinity which ranged from 22.6 to 34.9.This study concludes that wheat can be substituted by these flours in various applications.