Four series of konjac glucomannan esters (KGME) of long fatty acid are prepared by heterogeneous method.Differential thermal analysis (DTA) thermographs show the transitions of crystalline structure of KGME.With the increase of degree of substitution (DS) for palmitoylated konjac glucomannan (PKGM)

the samples show new crystalline states at higher temperature and the former crystalline state of konjac glucomannan (KGM) disappears.X-ray diffraction spectra indicate the effect of the length of acyl chain on the crystalline structure of KGME.At high DS of octanolylated KGM(OKGM)

dodecanolylatedKGM(DKGM)

PKGM and octadecenoylated KGM(OLKGM) the intercrystalline distances are 2.10

2.45

2.58 and 3.39nm

respectively

and the effect of DS of KGME on its emulsifying ability has been investigated in aromatic hydrocarbon in water and cycloalkane in water (O/W) emulsions.It is demonstrated that in the proper range of DS.KGME has good emulsifying ability in O/W emulsion

even in high salt concentration and in acidic pH.Clove oil-water (O/W) emulsion has good stability within four weeks at room temperature

and the breakage of emulsion was not brought about.