Physicochemical,Pasting, Thermal and Morphological Characteristics of Indian Water Chestnut (Trapa natans) Starch

Starch extracted from Indian water chestnut was investigated for its physicochemical characteristics. The results were compared with those obtained from two commercial starches (corn and potato). The pasting properties were tested in the Rapid Visco Analyser and thermal properties with a differential scanning calorimeter. Water chestnut starch possessed higher breakdown viscosity (BV) and setback viscosity (SV) than corn and potato starches. However, the pasting temperature of water chestnut starch was not significantly different from that of corn starch. Lower ΔH_gel values were obtained for water chestnut starch than for the other two starches whereas the onset, peak and conclusion temperatures of gelatinization (T_o, T_p and T_c) for water chestnut starch were quite comparable with corn starch. Scanning electron micrographs showed similarity in starch granule shape between water chestnut and potato starch with corn starch showing surface wrinkles on starch granule surfaces.