Thermal behavior of gum arabic in comparison with cashew gum

Thermal behavior of gum arabic and cashew gum, the exudate polysaccharides from Acacia and Anacardium occidentale L., containing different gum/water concentrations: 100/0, 80/20, 60/40, 50/50, 40/60, 20/80 and 5/95% w/w, were studied by differential scanning calorimetry (DSC) and thermogravimetry (TG). DSC thermal profiles for gum arabic with low water content (0–40%) showed an endothermic event at about 90°C (Tonset) and with increasing water content (50–80%) multiple melting endotherms and associated enthalpies were observed. Similar behavior was found in the DSC curves of cashew gum with Tonset of about 97°C. TG curves show two decomposition stages, the major decomposition occurred at 252°C (Tonset) to arabic and cashew gums pure.