The effect of various salts on the gelatinisation properties of sago starch has been studied using differential scanning calorimetry. The presence of salts affected the gelatinisation temperature, T_(gei) and gelatinisation enthalpy, AH depending on salts used and their concentrations. Generally in the presence of salting-out ions such as sulphate, T_(gei) increased with increasing salts concentration, while in the presence of salting-in ions such as thiocyanate and iodide, T_(gei) and AH decreased. For other salts such as sodium chloride, potassium chloride and sodium nitrate T_(gei) increased at low salt concentration and then decreased as the salt concentration increased while AH decreased with concentration. For salts such as calcium chloride, magnesium chloride and lithium chloride, at low concentration, T_(gei) increased slightly, then decreased to a minimum (~ 3M for CaCU, ~ 3M for MgCb and ~ 7M for LiCl) and increased again at higher salt concentrations and the transition became exothermic. The effect of salt concentration on the gelatinisation properties of other starches was also studied. Metal chloride salts appear to have similar effect on the gelatinisation of other starch types although the decrease in T_(gei) at high concentration was more pronounced for B-type starches (potato) compared to A-type starches (corn and tapioca). Sago starch which has a C_A-type structure behaved typically as A-type starches.
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