In the present study the effect of iodine on the structural characteristics (by infrared spectroscopy and X-ray) of films made from kidney bean starch was evaluated. The pasting properties as affected by iodine and glycerol were also evaluated. Kidney bean starch showed C-type (mixture of A- and B-type) crys_talline structure, the conversion of starch into films resulted into reduction in intensity of diffractograms. The starch powder FTIR spectra had peaks centered at 1020 and 995 cm~(-1) with a higher intensity at 1020 cm-1, which is consistent with a partially crystalline material since fully crystalline material show similar intensity peaks centered around 1020 and 1006 cm-1. Films without iodine showed one main peak centered around 1000 cm-1 consistent with a disordered state similar to that in gelatinised starch. Iodine addition gradually increased the intensity of the bands around 1020 cm-1 consistent with the formation of more ordered conformation similar to that in the crystalline material. Iodine encourages the forma_tion of helical structures, however, the formation of crystalline material cannot be inferred. The increasing amounts of iodine up to 0.33% level progressively increased the peak-, through- and breakdown-viscosity. Iodine beyond 0.33% level gradually decreased peak-, trough-, breakdown- and setback-viscosity. Pasting temperature gradually increased with the increase in iodine.
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