Microwave-assisted preparation of potato starch silicated with silicic acid

Application of microwave irradiation for the silication of granular potato starch with silicic acid, and the properties of silicated starch were investigated. Potato starch was esterified on 20 min microwave irradiation of starch with silicic acid, applying the power of 450 or 800 W and, for comparison, on 120 min convectional heating of the reagent blend at 100 °C. The degree of esterification and the reaction efficiency did not depend on the silication mode, but they increased with increasing power of the microwave irradiation. The degree of esterification increased with the reagent ratio. The esterification provided either monoesters or crosslinked esters of retained granularity, insignificantly disrupted crystallinity, and high hydrophobicity. An increased dose of silicic acid in the reaction mixtures provided thermally more stable crosslinked esters.