Study on Structure and Properties of Yam Starch-Guar Gum Blends
The effect of guar gum on the structure and properties of yam starch complex system is discussed.The rapid viscosity analyzer(RVA)results show that guar gum could increase the viscosity and disintegration value and decrease the retrogradation value of complex system,and shows a linear dependence with the increase or decrease of guar gum addition amount.The differential scanning calorimeter(DSC)shows that with the increase of guar gum proportion,the thermal transition temperature and enthalpy of the three different proportions of starch complex system increase,the expansion degree of starch complex system decreases gradually.The X-ray diffraction(XRD)analysis shows that the addition of guar gum leads to the destruction of crystal structure,and the gel network structure becomes more uniform and compact,resulting in the continuous increase of molecular density and the increase of relative crystallinity of complex system.Fourier transform infrared spectroscopy(FT-IR)shows that guar gum does not increase the new absorption peak,but the addition of guar gum changes the hydrogen bonding force of complex system and strengthens the short-range ordered degree.Guar gum can change the particle size distribution range of complex system.With the increase of guar gum proportion,the large particles in the sample molecules increase.