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Updated: Feb 16, 2026
Analysis and Specification of Starch Granule Size Distributions
Published on: March 4, 2021
Preparation of donut-shaped starch microparticles by aqueous-alcoholic treatment
Yousof Farrag1, Constanza Sabando2, Saddys Rodríguez-Llamazares2
1Universidade da Coruña, Grupo de Polímeros, Departamento de Física, Escuela Universitaria Politécnica, Serantes, Avda. 19 de febrero s/n, 15471 Ferrol, Spain.
Abstract:
A simple method for producing donut-shaped starch microparticles by adding ethanol to a heated aqueous slurry of corn starch is presented. The obtained microparticles were analysed by SEM, XRD and DSC. The average size of microparticles was 14.1 ± 0.3 μm with holes of an average size of 4.6 ± 0.2 μm. The crystalline arrangement of the microparticles was of a V-type single helix. The change in crystallinity from A-type of the starch granules to a more open structure, where water molecules could penetrate easier within the microparticles, substantially increased their solubility and swelling power. The microparticles exhibited a higher gelatinization temperature and a lower gelatinization enthalpy than did the starch granules. The donut-shaped microparticles were stable for more than 18 months and can be used as a carrier of an active compound or as a filler in bioplastics.
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