Rice starch has characteristics suitable to many industrial applications, however, the hydrophilic nature of the starch in native form may present some limitations for some uses. In this study, rice starch with medium amylose content was acetylated under alkaline catalysis on two reaction conditions to produce starch acetates with different degrees of substitution (DS). The introduction of acetyl groups to the starch was confirmed by infrared Fourier transform (FT-IR) and starch acetates produced were evaluated for their paste properties in viscoelastograf (RVA). Acetylation caused reductions in all properties paste (paste temperature, minimum viscosity, peak viscosity, final viscosity and retrogradation tendency) being the most intense reduction in acetylated starch with greater GS.
Acetylation; Chemical modification; Viscosity; Retrogradation; RVA