The Physicochemical, Morphological, Functional, Thermal Properties, and Digestibility of Amaranthus paniculatus (Rajgeera) Starch and Flour

Abstract

AbstractThe present study aims to characterize the physicochemical, morphological, functional, thermal properties and in vitro digestibility of Amaranthus paniculatus flour (APF) and A. paniculatus starch (APS). A significant difference (p ≤ 0.05) is observed in the chemical composition of A. paniculatus flour and starch; the amylose content of the starch (3.91%) is found to be significantly higher (p ≤ 0.05) than flour (2.35%). Morphology of APS reveals that the starch granules are polygonal, have a smooth surface, and have no fissures. A. paniculatus flour and starch exhibit A‐type crystallinity; however, the relative crystallinity of APS (15.75%) is significantly higher (p ≤ 0.05) than flour (12.76%). The functional properties, including solubility, water and oil absorption capacity of APF are significantly higher (p ≤ 0.05) than APS. The enthalpy of gelatinization (ΔH) of APS is found to be significantly higher (p ≤ 0.05) than APF. A. paniculatus starch has a significantly higher (p ≤ 0.05) amount of rapid digestible starch (RDS) than flour, however, the flour of A. paniculatus has significantly higher (p ≤ 0.05) resistant starch (RS) and slowly digestible starch (SDS). The study reveals that A. paniculatus flour and starch are significantly different from each other and can be used in various food and non‐food industries due to their physicochemical, functional, and structural properties.