Caracterização do amido isolado de diferentes cultivares de sorgo (Sorghum bicolor L. Moench)

Abstract

Starch is a polymer that can be extracted from sources such as roots, tubers and cereals, among which, sorghum stands out. Its functionality depends on the genetic origin and the planting conditions. The objective of this work was to characterize the starch of different sorghum cultivars (BR 501, BRS 305 and BRS 310) in terms of centesimal composition, color, water solubility index (WSI) and water absorption index (WAI). The levels of total carbohydrates, ashes and proteins, varied according to the type of sorghum, with no difference in relation to the moisture and lipid content. The centesimal composition of the starches indicated its high purity, since it had low levels of proteins, lipids and ash. Regarding color, cultivars BR 501 and BRS 310 showed a higher degree of luminosity (L = 95.61 and 95.86) compared to BRS 305 (L = 91.23). The three showed high luminosity, characterizing white color, desirable for starch. However, the BR501 showed an angle hue = 77.90, expressing a color trend towards light brown, but with low intensity (Chroma = 3.49); BRS 305 expressed a color trend towards light pink (h = 59.86) of low intensity (C = 6.47) and BRS 310 light pink color (h = 58.84), of lower intensity compared to the previous one ( C = 5.68). Regarding ISA and IAA, obtained at temperatures of 65, 75, 85 and 95 ° C, it was found that the swelling power and water solubility of starches were similar and increased with the temperature rise. The studied starches showed differences according to the sorghum genotype used, in relation to the proximate composition and color, not differing in relation to the properties of swelling and solubility in water.