Morphological, physicochemical and functional characteristics of starch from Marantha ruiziana Koern

- Starch isolated from the Amazonian plant Marantha ruiziana Koern was characterized.
- A-type X-ray diffraction pattern like cereal starches was displayed.
- High peak viscosity and thermal stability was found for isolated starch.
- The main drawback of the marantha starch is a high tendency to retrogradation.

Marantha ruiziana Koern (MrK) is an Amazonian plant with starchy rhizome, which can be used as an alternative botanical source for starch isolation. The morphology, crystallinity, short molecular order, pasting and thermal properties of MrK starch were assessed and compared to cassava starch, a rhizome that is also harvested in the Amazonian region. The amylose content of MrK starch was 29.0%, and the granule size diameter was in range from 9.7 to 24.0 μm. Starch granules exhibited polyhedral shapes with irregular polygonal surfaces. X-ray diffraction analysis revealed A-type crystallinity with about 26.1% of crystallinity content. X-ray diffraction and Fourier transform infrared spectroscopy evidenced reduced molecular order of MrK starch compared to cassava starch, although the gelatinization and pasting temperatures were higher in MrK starch. Also, MrK starch pastes showed high tendency to retrogradation after seven days of storage at 4.0 °C as assessed by differential scanning calorimetry. Overall, the results showed that MrK starch has interesting characteristics (e.g., high peak viscosity, thermal stability) that can be exploited for applications in food and non-food products.