EFFECT OF THE ACETYLATION DEGREE ON THE MORPHOLOGICAL AND PHYSICOCHEMICAL CHARACTERISTICS OF BANANA STARCH

The morphological and physicochemical characterization of acetylated banana starch with low (ABSLDS) and high (ABSHDS) degree of acetylation was carried out. Fourier transformed infrared spectroscopy indicated that banana starch showed a band at 1740 cm(-1) that corresponds to stretching of C-O in the acetyl groups. Morphological studies demonstrated that a higher damage in the starch granules occurred as the degree substitution was higher. This effect was more notorious in the pasting profile because the ABSHDS did not exhibit the viscosity peak, breakdown and setback parameters. The average gelatinization temperature was similar in the native sample and in the ABSLDS, but was lower in the ABSHDS. The enthalpy of gelatinization was low in the ABSHDS, indicating a higher disorganization of the double helices in the amylopectin due to higher degree of acetylation. As the degree of acetylation increased the retrogradation decreased. Banana starch with different acetylation degrees possess varied physicochemical properties that provide them with potentially wide applications spectra.