Physico-chemical, morphological, pasting and thermal properties of stem flour and starch isolated from kithul palm (Caryota urens) grown in valley of Western Ghats of India

Starch is the major component of kithul flour (66%) obtained from the trunk of kithul palm (Caryota urens). In this study, physicochemical, morphological, pasting and thermal properties of kithul flour and starch were compared. It is a high amylose starch (38.5%). Kithul starch has higher phosphorous content than some of the tubers and legume starches. Kithul starch is oval in shape with smooth surface and showed higher swelling index and solubility than flour. Kithul starch showed type A crystalline pattern with 34.2% relative crystallinity. Water and oil absorption capacity of kithul flour is higher than that of starch. Kithul starch showed higher pasting properties such as peak, trough, setback and final viscosity as compared to flour. Sharp increase in peak viscosity showed rapid swelling character of kithul flour and starch. As compared to flour, kithul starch gel has higher firmness. Kithul starch showed higher gelatinization (onset, peak and conclusion) temperature and enthalpy of gelatinization as compared to flour.