Characterisation of native starches of seeds of Araucaria angustifolia from four germplasm collections

Germplasm is a source of genetic variability available for plant breeding. These techniques have become accessible and necessary to protect biological diversity. The collections are groups of representative genotypes with the genetic variability of the species that is the object of conservation. Four samples of pinhao, obtained from Parana pine seeds, were supplied by EMBRAPA Florestas (germplasm bank). Starch was carefully extracted in aqueous solution, whose yield was around 32.5%. For each sample the gelatinisation temperature (T-p) occurred below 63.6 degrees C and gelatinisation enthalpy (Delta H-gel) was different for each sample. TG-DTA curves showed similarity, although with mass losses and peaks at different temperatures. The pasting temperature obtained by RVA was directly proportional to the onset and peak temperatures obtained by DSC. The XRD technique allowed the degree of relative crystallinity to be calculated for each sample. From the results it can be verified that each sample had specific characteristics. Crown Copyright (c) 2013 Published by Elsevier B.V. All rights reserved.