Fortified Rice Starches: The Role of Hydrothermal Treatments in Zinc Entrapment

• Published in: Starch - Stärke Vol. 71; no. 1-2
• Main Authors: Henning, Fernanda Gabriela, Schnitzler, Egon, Demiate, Ivo Mottin, Lacerda, Luiz Gustavo, Ito, Vivian Cristina, Malucelli, Lucca Centa, da Silva Carvalho Filho, Marco Aurélio
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01.01.2019
• Subjects: ANN; Cations; Crystal structure; Crystallinity; Enthalpy; Entrapment; fortified foods; Heat treatment; HMT; modified starch; Oryza; Photomicrographs; physical treatment; Precursors; Proteins; Rice; Stability analysis; Starch; Starches; Thermal properties; Thermal stability; Thermodynamic properties; Viscosity; Zinc
• ISSN: 0038-9056; 1521-379X
• DOI: 10.1002/star.201800130

This study investigates the potential for zinc fortification of native, heat‐moisture treatment (HMT), and annealing (ANN), modified rice starches, using neutral extracted rice starch as precursor. The zinc content, micrographs, X‐ray crystallinity, pasting, and thermal properties are evaluated. The fortified rice starch increases crystallinity, thermal stability, and gelatinization enthalpy, as well as lowers peak viscosity and gelatinization temperature when compared to its precursor (native rice starch). The ANN fortified starch shows decreased crystallinity, thermal stability, gelatinization temperature, and enthalpy, while the HMT starch has increased crystallinity and final viscosity. The results indicate that the native rice starch has higher zinc entrapment potential (1359 mg Kg−1) than the physically modified starches (<100 mg Kg−1); this is attributed to the protein spread over the surface of the granules and the pre‐gelatinization of the surface of the starches after modification, which serve as a barrier to zinc cations. This study investigates the potential for zinc fortification of native, heat‐moisture treatment (HMT), and annealing (ANN) modified rice starches. The native rice starch has higher zinc entrapment potential (1359 mg Kg−1) than the physically modified starches (<100 mg Kg−1); this is attributed to the protein spread over the surface of the granules and the pre‐gelatinization of the surface of the starches after modification.