Impact of Knife, Disc, and Ball Milling on the Structure and Functionality of Quinoa Flour.

Abstract

This investigation focuses on optimising the milling processes of white quinoa (<i>Chenopodium quinoa</i> Willd.) to enhance its industrial applications. Three milling technologies-knife, disc, and ball milling-were employed to produce flours characterised by various physicochemical analyses. The granulometric analysis indicated that ball milling achieved the finest particle size distribution, significantly improving water absorption capacity and dispersion. Mathematical modelling confirmed that the Rosin-Rammler-Bennett model provided superior predictive capability for rheological behaviour (R² > 0.9624). X-ray diffraction revealed a reduction in crystallinity as milling progressed, while differential scanning calorimetry indicated a decrease in gelatinisation enthalpy and temperature range, suggesting enhanced thermal processing efficiency. Ball milling of the quinoa flour resulted in marked structural changes, as observed by electron microscopy, which are associated in the literature with potential benefits for technological applications in gluten-free and health-oriented foods. Furthermore, fractionation of the flours yielded nutrient-rich bran, containing high levels of protein and fibre. These findings establish critical processing-structure-function relationships, promoting the scalable production of high-value quinoa ingredients that cater to the increasing demand for sustainable and health-oriented food solutions.