CARACTERIZAÇÃO FÍSICA E FÍSICO-QUÍMICA DE RIZOMAS E AMIDO DO LÍRIO-DO-BREJO (Hedychium coronarium)

Abstract

The objectives of this research were to evaluate the chemical composition of Hedychium coronarium rhizomes and isolate and characterize their starch by conducting physical and physicochemical analyses. The chemical composition of isolated starch granules was also determined, as well as shape, size, particle distribution size by laser diffraction, paste viscosity by rapid visco-analysis, swelling power, water solubility index, thermal property by differential scanning calorimetry, and crystallinity by X-ray diffraction. Rhizomes presented high water content and low lipids, carbohydrates, ash, protein and fiber levels. Due to its low dry matter content (17.3%), with 21.97% of starch, as well as long fibers and latex, which hamper starch extraction, the white ginger lily rhizomes are not interesting as a starch source. The isolated starch showed 99.2% purity, with 37.2% of amylase content. The starch granules presented an irregular polyhedral shape and average size of 38.2 ? m . The crystalline structure of the starch granules was type A, which is maintained by strong internal associative forces that reduce water solubility. The starch gelatinization temperature occurs between 73.1oC and 78.7°C. The starch paste viscosity profile showed high stability at 95°C and high tendency to retrograde, suggesting its use in adhesive and food industries. KEY-WORDS: Hedychium coronarium ; physicochemical and functional properties; paste viscosity; starch thermal property.