Impact of ball milling on physicochemical, structural, and functional properties of Moringa oleifera L. leaf powders

Abstract

Physicochemical, thermal, and structural properties of ball milling (BM) of Moringa oleifera leaf powders (M.L) were examined. By superfine grinding, three samples with different particle sizes (PAS) were produced. Specific surface area (SSA), Bulk (BD), tap (TD) densities and water solubility index (WSI) significantly increased with the decrease of PAS, while the angle of repose (AR), water holding capacity (WHC) and oil holding capacity (OHC) decreased. Also, as PAS was reduced, the flowability enhanced as the carr index changed from fair to good and AR ameliorated. Scanning electron microscopic (SEM) pictures showed that M.L were ground so finely that the form of the particles changed, started to be a regular shape and the surface roughness decreased as PAS decreased. Differential scanning calorimetry (DSC) curves showed that peak temperature decreased with the decrescent PAS. In all samples, Fourier transform infrared spectroscopy (FT-IR) detected no new chemical functional groups. No variation was found in the crystallinity index (CI) of any of the X-ray diffraction (XRD) patterns for the BM samples, while crystal size decreased.