Effects of single and dual heat-moisture treatment combined with sodium alginate on the physicochemical properties of normal cornstarch

•Single (SHMT) and dual heat-moisture treatment (DHMT) were used in modified starch.•SHMT and DHMT affected the property of sodium alginate-normal cornstarch (AG-NCS).•Treated AG-NCS processed the property of anti-shearing and anti-retrogradation.•SHMT had the most remarkable effect on pasting property of AG-NCS.•Among all the samples, AG-NCS after DHMT-20 showed the lowest RC value.

Modified starch is considered to be an important ingredient in the application of food industry. The present study investigates the physicochemical properties of normal cornstarch (NCS) treated with a single heat-moisture treatment (SHMT) or a dual heat-moisture treatment (DHMT) with an interval storage temperature of 25 °C (DHMT25), 4 °C (DHMT4) and −20 °C (DHMT-20) in the presence of sodium alginate (AG). The results showed that both SHMT and DHMT combined with AG increased the pasting temperature (PT), gelatinization conclusion temperature (Tc), gelatinization temperature range (Tc-To), and gel hardness of NCS, but they decreased the pasting viscosities, gelatinization onset temperature (To), gelatinization enthalpy (ΔH), and relative crystallinity (RC) of NCS. Neither SHMT nor DHMT combined with AG addition changed the crystalline type of NCS. Sodium alginate-normal cornstarch (AG-NCS) mixtures after SHMT showed the highest PT value and gel hardness, and they showed the lowest breakdown (BD) and setback (SB) values, indicating that AG-starch mixtures with SHMT had superior mechanical and thermal stability. AG-NCS after DHMT-20 showed the highest Tc and Tc-To values as well as the lowest ΔH and RC values, suggesting that the hydrothermal treatment had an effect on the structure changes of starch molecules. Above all, both SHMT and DHMT had effects on the properties of AG-NCS.