Physicochemical, functional, textural and colour characteristics of starches isolated from four taro cultivars of North-East India

Physicochemical, functional, textural and colour characteristics of starches from four North-East Indian taro cultivars namely, Ahina, Muktakashi, JCC37 and JCC57 were examined. The starch granules were irregular and polygonal in shape and average size of the granules varied from 2.49 to 3.29 µm. All the cultivars presented A-type XRD pattern, which is a characteristic of cereal starches. The FT-IR spectra obtained for the four starch samples were similar in the form and intensity of the major peaks. The gelatinization temperatures (Tp) of Ahina, Muktakashi, JCC37 and JCC57 starches were 73.33, 70.61, 83.33 and 80.01°C, respectively. The Tp of JCC37 and JCC57 were much higher compared to Ahina and Muktakashi starch. The swelling and solubility of the starches were not much different from each other and were comparable to rice starch. Pasting temperatures of the starch pastes ranged from 83.3 to 87.2°C and were higher compared to rice or taro starches reported by other authors, but were closer to maize starch. The starch pastes had less lightness and texture was found to be less firm. Freeze–thaw stability of the starch gels were poor making it unsuitable for foods subjected to refrigeration.