Abstract

EFFECT OF CHEMICAL MODIFICATION ON THE PROXIMATE COMPOSITION OF PLECTRANTHUS ESCULENTUS STARCH AND CHARACTERIZATION USING FTIR SPECTROSCOPY

Kemas, U.C., Nep, E.I*., Agbowuro, A.A., Ochekpe, N.A.

Faculty of Pharmaceutical Sciences, University of Jos, Jos-Nigeria.

Abstract

Starch from tubers of P.esculentus was extracted and chemically modified using four different methods which includes HCl-ethanol treatment, dry heating or dextrinization at 200oC, xerogel formation, and gelatinization of the starch. Structural changes in native starch and the derivatives were elucidated using Fourier Transform Infrared Spectroscopy (FTIR). Also the effect of the chemical modifications on the proximate compositions of the starch was evaluated. The results showed that the crude protein content was lowest for the dextrinized starch (0.58%). while crude lipid was lowest (0.05%) in the HCl-ethanol hydrolysed starch derivative. The ash content was 1.5 and 2.0% in the xerogel and HCl-ethanol hydrolysed starch derivative respectively. FTIR spectrospic analysis revealed substantial structural variations between the different derivatives of the native starch. Chemical modification of native P. esculentus starch resulted in derivatives which significantly differ from the native in proximate composition and structure. Significant variations in the functionality of the starch derivatives may be expected.

Keywords: P.esculentus starch, chemical modification, proximate composition, characterization, FTIR spectroscopy.