Behavior of Pasting Properties of Ohmic‐Heated Corn Starch Versus Moisture and Temperature Applied

Abstract

AbstractStarch is an essential biopolymer for creating viscous food systems in the food industry. Viscosity behavior is unclear in the literature and varies with the thermal process and moisture content used. This study analyzed how ohmic heating affects the pasting properties of corn starch in response to changes in moisture and temperature. Corn starch is mixed with water at varying ratios (1:1, 1:3, and 1:5). The mixture is heated at 5 °C min−1 using an ohmic heating cooker to 80, 100, and 120 °C. Moisture affects pasting and starch properties. Peak viscosity varies with moisture content, decreasing from 5904 cP (native) to 3204–4510 cP at a 1:1 ratio. At a moisture ratio of 1:3, peak viscosity matched the native sample. Higher peak viscosity (6539 to 8772 cP) occurred at high moisture levels (1:3). Thermal properties confirmed different gelatinization degrees, which is evidenced by a shift in the x‐ray diffraction pattern from A‐type (native starch) to V‐type crystalline. The viscosity and physicochemical properties of corn starch depend on temperature and moisture levels. Moisture has a more significant impact on these properties than temperature. Therefore, varying the moisture content it can improve corn starch properties precisely, making it useful for the food industry.