Isolation and Characterization Studies of Ginger (Zingiber officinale) Root Starch as a Potential Industrial Biomaterial

Abstract

Ginger (Zingiber officinale) roots were crushed and the starch extracted in order to determine its starch composition and use in biomaterials development as hybrid composites. The physicochemical properties of the isolated starch were then determined and compared with standard industrial maize starch. The starch was isolated using 1% w/v sodium metabisulphite solution and the obtained starch was found to be a white, crystalline, non- hygroscopic powder with yield of about 18%. The starch percentage solubility at 90˚C was 1.87 with a swelling power of 11.07 and gelatinization temperature of 78˚C. It had a browning temperature of 243.5 - 248.2˚C, charring temperature of 278.6 - 285.2˚C, water absorption capacity of 90%, pH of 6.54, foam and emulsion capacities of 2.5% and 5.7% respectively. XRD analysis of the starch sample at 10˚C - 100˚C 2Θ angle showed the starch to be a polycrystalline organic polymer of pharmaceutical/medicinal grade. The percentage composition of amylose to amylopectin was found to be in the ratio of 32% to 68% with an orthorhombic crystal structure. The profile revealed peak positions at 2Θ positions of 11.2282˚, 15.0054˚, 17.0346˚, 18.0121˚ and 22.8782˚ corresponding to a Full Width at Half Maximum (FWHM) (2Θ) of 0.7911˚, 0.5274˚, 0.4615˚, 0.6593˚ and 0.5934˚ respectively. The spectral of the ginger starch sample corroborate with standard corn starch which served as the reference with a quality score of 82%. Applicability in composite materials studies showed a high level of compatibility as binder/filler materials within the matrix and fibre materials employed. Generally, the values obtained from the characterization of ginger starch compared favourably with corn starch and showed that it has high potential for industrial applications as biomaterials in composites, food, textile and pharmaceutical industries.