Physicochemical properties and antioxidant capacity of debranched starchferulic acid complexes

Amylose, a primarily linear polysaccharide of (14)--D-glucose units, displays a folding in a helical conformation and has an ability to form an inclusion complex with a variety of ligands. In this study, debranched starchferulic acid complexes were produced by adding ferulic acid to the debranched cassava starch paste and their physicochemical properties and antioxidant capacity were investigated. The mixing ratios of ferulic acid to starch were 0.02 (DS-FA0.02), 0.05 (DS-FA0.05), and 0.10g ferulic acid/g starch (DS-FA0.10). The amounts of bound ferulic acid in the DS-FA0.02, DS-FA0.05, and DS-FA0.10 were 6.8, 16.2, and 31.5mg/g starch, respectively. The ferulic acid was observed to be entrapped in the hydrophobic core of double helices, which did not affect the crystalline structure, gelatinization temperatures, viscosity, and RS content of the crystallites formed by the linear-chain molecules of the debranched starch. The solubility and antioxidant capacity of the debranched starchferulic acid complexes increased with increasing in amount of bound ferulic acid in the complexes. The higher RS content and antioxidant capacity of the complexes are considered to have significant benefits for human health. Therefore, the debranched starchferulic acid complexes might be used as a new functional food as well as pharmaceutical products.