Potential of taro starch spherical aggregates as wall material for spray drying microencapsulation: Functional, physical and thermal properties

Taro starch spherical aggregates have been considered as wall material for the microencapsulation of bioactive compounds. The distribution of particle size, morphology, stability, glass transition temperature, ζ-potential, physical properties and flowability and compression indexes, and functional properties (water, oil and dye retention capacity) were measured. The average diameter was 17.5 ± 0.3 μm. Aggregates formed by a relatively high number of starch granules were observed. The residual protein in the aggregates was in the periphery of the starch granules, favoring the aggregation and the stability under aqueous stirring conditions. The ζ-potential was −21.8 ± 0.3 mV. The value of the glass transition temperature was in the range from 176.8 to 75.4 °C, with 5% and excess water, respectively. The Hausner ratio and Carr index were 1.06 and 14.7, respectively. The oil holding capacity was 1.2 ± 0.01 g of oil·g⁻¹ of dry solid. Overall, the functional, physical and thermal properties of the spherical aggregates of taro starch granules showed that this material offers good potential for the microencapsulation of bioactive compounds.