Effects of Anthocyanin on Physicochemical Properties of Starches with Different Amylose Contents

The effects of anthocyanin on the physicochemical properties of starch were investigated. Anthocyanin (0%, 1%, 2%, 5% and 10% based on starch weight) was added to starches with different amylose content. The results showed that the iodine binding capacity, apparent viscosity and viscoelasticity of starch decreased with the increasing of anthocyanin contents, and this decreasing trend was positively correlated with amylose contents. With the concents increasing of anthocyanin, the gelatinization temperature and enthalpy value gradually decreased. When the anthocyanin concentration was 10%, the gelatinization enthalpy value of the three systems decreased by 23.92%, 44.91% and 59.89%, respectively. Starch-anthocyanin system showed a similar infrared spectrum as original starch, but the bands at about 3400 cm^-1 were shifted to lower wavenumber in the system. In addition, the crystallinity of starch decreased with the addition of anthocyanin, and when the anthocyanin concentration was 10%, the crystallinity of the three systems decreased by 7.99%, 15.49% and 24.87%, respectively. The scanning electron microscopy results showed the addition of anthocyanin made the micromorphology of starch showed loose and porous. To sum up, the above results demonstrated the marked effect of anthocyanin on the physicochemical properties of starch, and this effect was related to amylose contents. In this study, the effect of anthocyanin on the physicochemical properties of starch were investigated, in order to provide theoretical basis as anthocyanin in starch the application