Resistant starch-rich powders prepared by autoclaving of native and lintnerized banana starch:: Partial characterization

Powdered preparations enriched in resistant starch (RS) were obtained from native and lintnerized (prolonged acid treatment) banana starches by consecutive autoclaving/cooling treatments. The preparations were tested for indigestible starch content, swelling and solubility properties, thermal analysis and pasting profile. The autoclaved samples had higher RS content than their parental counterparts, but the chemical modification (lintnerization process) allowed development of higher RS proportions (19%, dry matter basis, dmb). The autoclaved samples (RS-enriched products) showed similar swelling values (alpha = 0.05) at the temperatures assessed. These RS-rich products exhibited a lower solubility in water than the corresponding raw materials. The peak temperatures of the thermal transition were 155.5 and 145.8 degrees C for native autoclaved and lintnerized autoclaved starch, respectively. These values indicate that RS products have a marked thermal stability. The pasting behavior of the RS products was less pronounced than that of the raw counterparts. Hence, their potential use as processed food ingredients should not impact final product viscosity. These RS-enriched products appear suitable for the formulation of functional foods.