Modification of hydrophobic properties of konjac glucomannan using octenyl succinic anhydride

Konjac glucomannan (KGM) is a water-soluble polysaccharide that has the potential to be used as a natural emulsifier because of its high viscosity. This study aimed to modify the KGM structure in order to obtain a KGM which has amphiphilic properties. Modifications were carried out in the microwave using 1-3% sodium carbonate (Na2CO3) and 2-4% octenyl succinate anhydride (OSA). Parameters observed included emulsion capacity, emulsion stability, degree of substitution with High-Performance Liquid Chromatography (HPLC), viscosity, hydrophobicity, and Fourier transform infrared Spectroscopy (FT-IR). The results showed that the interaction between the concentration of Na2CO3 and OSA had a significant effect on the capacity and stability of the octenyl succinic anhydride-modified konjac glucomannan (KGOS) emulsion. The highest emulsion capacity and stability were obtained using 2% Na2CO3 and 4% OSA. OSA esterification of KGM was shown by increasing the degree of substitution, viscosity, hydrophobicity, and FT-IR analysis. Thus, KGOS can be used as a natural emulsifier with good amphiphilic properties.