No abstract

The effect of octenyl succinic anhydride (OSA) esterification (1%-3% of dry starch) on powder flowability, functionality, pasting, and gel rheological properties of buckwheat starch (BS) was examined. The physical and flow properties like bulk density, tapped density, Hausner's ratio, Carr's index, cohesion index, and caking strength of starch improved significantly after esterification, indicating better flow behavior and storage stability. The solubility and swelling power were significantly increased, leading to a significant increase in peak viscosity and breakdown, while pasting temperature, setback, and final viscosity decreased. The esterification also restricted the retrogradation, which appeared as a lower hardness of retrograded gel. Starch gel prepared at 5%, 10%, and 15% concentrations showed shear thinning behavior. The dynamic shear properties obtained within the linear viscoelastic region showed weak gel behavior with a more elastic nature and were also demonstrated by the Power law.

No abstract

In the present study, Guinea seed starch (GS) is extracted using four different isolation methods (Sodium hydroxide [NaOH], potassium metabisulphite [KMS], citric acid [CA], and distilled water [DW]) to investigate the effect of isolation methods on different properties of starch. The water and oil absorption capacity range from 0.69 to 1.12 g g −1 and 0.81 to 0.95 g g −1 , respectively. The swelling and solubility of isolated starches are temperature dependent and increase with temperature (70-90 °C). The amylose content also varies with isolation method and all the starch showed typical A-type X-ray patterns. The mean particle size of GS is 9.86-13.36 µm and shows round to polygonal shapes with pores. The isolation method impacts glass transition temperatures and enthalpies, which vary between 73.36-83.67 °C and 0.72-23.69 J g −1 , respectively. The pasting temperature (PT) also varies with the isolation method and follows the pattern of CA (84.80 ± 0.07 °C) > KMS (81.97 ± 0.06 °C) > DW (81.95 ± 0.05 °C) > NaOH (79.82 ± 0.03 °C). All the starches showed shear thinning behavior, and storage modulus is higher than loss modulus, representing that the elastic component is higher than the viscous component.