Spectroscopic determination of the degree of esterification of pectic substances from kenaf

Pectins were isolated from bark, wood and pith of four kenaf (Hibiscus cannabinus L.) varieties. The degree of esterification of isolated pectins was studied using Fourier transform infrared spectroscopy. It was determined as being between 57 and 90% and there were no notable differences between kenaf varieties. The higher value of the degree of esterification was presented in wood pectins (86-90%), the interim in pith (75-83%) and the lower in bark (57-64%).