Physicochemical and rheological properties of starches substituted with type 4 resistant starch (cross-linked corn starch)

Abstract

The physicochemical and rheological properties of native starch (corn (CS), rice (RS), potato (PS), tapioca (TS), and wheat (WS)) from different sources substituted with RS type 4 (RS4) at different concentrations (0, 20, and 50%) were determined. Swelling power and solubility of all native starch-RS4 mixtures proportionally decreased with the increase of RS4 concentration. Also, the peak viscosity and breakdown of starch-RS4 mixture decreased with increasing concentrations of the RS4 used. However, the setback viscosity decreased significantly for CS-RS4, TS-RS4, and WS-RS4, but it remained unchanged for PS-RS4. All native starch-RS4 mixtures exhibited decreased viscosity with increasing RS4, which could be well characterized by the Power-law model. Furthermore, dynamic oscillatory tests indicated that the native starch and RS4 mixtures exhibited less elastic properties with more frequency dependence, compared to native starch alone. Hardness for CS-RS4, RS-RS4, PS-RS4, and WS-RS4 gel decreased with increased storage time, whereas TS-RS4 did not.