Abstract

LEONEL, Magali. Analysis of the shape and size of starch grains from different botanical species. Ciênc. Tecnol. Aliment. [online]. 2007, vol.27, n.3, pp. 579-588. ISSN 1678-457X.  http://dx.doi.org/10.1590/S0101-20612007000300024.

An analysis was made of the shape and size of starch grains from different botanical species, aiming to improve the potential applicability of these species as starch raw materials. The starches were obtained from the processing of tubers in a pilot extraction plant. The shape of the starch grains was analyzed by scanning electron microscopy (SEM), to which end the samples were mounted on SEM stubs and coated with gold. The size of the starch grains was determined by optical microscopy, for which the samples were diluted in a water and glycerin solution. The sizes of 500 grains of each botanical species were measured to determine the largest and smallest diameters and the difference between diameters. The results revealed different starch grain shapes and sizes, with Xanthosoma sp showing the smallest (12.87 µm) and Canna edulis the largest grain size (56.61 µm). The yam bean tuber Pachyrhizus ahipa showed the most uniform starch grain distribution.

Keywords : starch; roots; microscopy.