Physical and Thermal Properties of <i>Zingiber officinale</i> Rosc. (Ginger) Rhizome Fine Particle as a Function of Grinding System

Abstract

In this study,Zingiber officinale(ginger) rhizome fine particles were prepared by using food processor, hammer mill and planetary ball mill and tested for their physical and thermal properties. The physical changes by means of particle size, surface morphology, FT-IR and thermal stability (TGA) were investigated. The size reduction method had a distinct effect on physical and thermal properties of ginger rhizome tested. Average particle size of ginger rhizome after using food processor and hammer mill was around 50µm and 20µm respectively while after using planetary ball mill the ginger rhizome was successfully reduced to nanoscale (222.3 nm). Higher degree of granule surface fractured was observed as a result of a planetary ball milling process based on FESEM images. There were also some notable differences of FT-IR spectra detected. By comparing the spectra, the stretching vibration peak of OH at 3292 cm-1[U1]and the symmetric stretching vibration peak of the NO2and C=C at 1369 – 1639.51cm-1 for ginger rhizome ground using food processor were disappeared. Yet, presence of possibly strong alkenes group (in the range 2850 – 2970cm-1) were observed in all samples tested. Ginger rhizome particles obtained from hammer milling process were found to be more stable to thermal effect where the decomposed temperature was 276.64°C as compared to samples milling using food processor and planetary ball mill. These results would provide useful insight for exploring the potential applications of ginger rhizome fine powder as functional food ingredient as well as in pharmaceutical applications. [U1]Check typing of superscript.