Effect of sucrose on the textural properties of corn and wheat extrudates

Extrudates were prepared by twin-screw extrusion at industrial scale. Sucrose in concentrations between 0 and 12.5% by weight was added to corn and wheat flours prior to extrusion. The effect of this ingredient on textural properties of the final products has been investigated. The resulting data revealed the following significant features: (1) the internal structure of the extrudates evaluated by image analysis showed a reduction of the cell size with the sucrose whatever the flour; (2) the crispness of products evaluated by puncturing increased with the sucrose content until an optimum whatever the flour; (3) the addition of sucrose in corn and wheat mix reduced overall product expansion; and (4) increasing the amount of sucrose in the mix induced greater molecular degradation of corn starch than of wheat starch.