Effect of Industrial-Scale Microfluidizer Treatment on the Physicochemical Properties and Quality of Whole-Component Dehulled Foxtail Millet Slurry

The effects of an industrial-scale microfluidizer (ISM) on the physicochemical properties and quality of whole-component dehulled foxtail millet slurry were investigated under varying processing pressures (0, 60, 90, and 120 MPa). ISM treatment significantly enhanced the apparent stability of the whole-component dehulled foxtail millet slurry, with ISM-120 exhibiting the best apparent stability. The results of dispersion characteristics, serum cloudiness, and zeta potential measurements indicated that ISM processing enhanced the physical stability of the slurry. As processing pressure increased, the particle size of whole-component dehulled foxtail millet slurry first decreased sharply and then showed a slight increase. Compared to the untreated slurry, the D was reduced by approximately 81.32%, 81.72%, and 78.44% after treatment at 60, 90, and 120 MPa, respectively. Concurrently, the apparent viscosity of the slurry rises with increasing processing pressure, with ISM-120 displaying the highest apparent viscosity. Furthermore, CLSM analysis revealed that ISM-90 and ISM-120 exhibited overall more uniform and stable structures. The content of damaged starch correspondingly increased with higher processing pressures, further corroborating the findings from particle size and scanning electron microscopy observations. Simultaneously, the soluble solids content also increased with rising ISM processing pressure. However, increasing ISM processing pressure progressively reduced the L*, a*, b*, and C* values of the slurry, while the ΔE and h values progressively increased. Compared to the untreated slurry, the ΔE value increased by approximately 1.92%, 3.85%, and 6.41% after treatment at 60, 90, and 120 MPa, respectively. These changes resulted in a deterioration of the color quality of the whole-component dehulled foxtail millet slurry.