The effect of infrared-assisted thermal and hydrothermal treatments on low-quality wheat flour obtained from tail-end passages and cracker quality

Abstract

Low-quality wheat flour (LQF) is a by-product with high nutritional value but poor shelf life and technological properties. In this study, infrared (IR)-assisted thermal and hydrothermal treatments were applied to stabilize LQF and improve its functional properties. For the hydrothermal treatments, LQF was adjusted to 15%, 20%, 25%, and 30% moisture content. Samples were processed at 800 W IR emitter power until moisture content dropped below 8%.

While the treatments had little effect on the core composition of the flour, they led to an increase in its maximum, final, and setback viscosities. Thermal treatment increased water absorption and solvent retention capacity, shortened dough development time (DDT), and did not affect extensibility. Hydrothermal treatments, however, led to an increase in extension resistance and DDT. The 15% initial moisture content improved dough stability and extensibility, but these characteristics declined at higher moisture levels.

In crackers produced from the treated flours, increasing initial moisture levels improved the spread ratio, though moisture levels of 25–30% reduced hardness and created a brittle texture. These findings revealed that varying initial moisture levels allowed for selective modifications in the stabilization of LQF, with acceptable changes in color and composition.