Abstract:
Konjac glucomannan (KGM) is one of the main components in konjac tuber. The deacetylation of KGM can improve its thermal stability and form irreversible gel with high elasticity, so that KGM can be used in food, materials, medicine and other fields. Considering the importance of deacetylation to the properties and industrial application of KGM, the effects of acetyl group on the solubility, crystallinity, conformation and other physicochemical properties of KGM are reviewed. The methods of removing acetyl group from KGM by alkali and its combination with mechanical and heating conditions are summarized. The characterization techniques of KGM deacetylation are systematically compared based on Fourier transform infrared spectroscopy, fluorescence spectroscopy, rheology, diffusion spectroscopy, scanning electron microscopy, atomic force microscopy, X-ray diffraction, thermal analysis, dynamic light scattering and so on. On these basis, the formation mechanism of KGM deacetylated gel as well as the influence of KGM concentration, alkali type and concentration, temperature, salt and ethanol on KGM gelation are elaborated and analyzed. Finally, the exploratory application of deacetylated KGM is listed and its future research direction and application are prospected, aiming to provide detailed reference for further KGM research and industrial application.
