Perspectivas de uso de almidones nativos de raices y tuberculos en relacion con sus propiedades especificas

Starches from several different Andean root and tuber sources have been studied (Cassava, Queensland Arrowroot, Ullucu, Arracacha, Yam Bean, Yarn, Oca). The starches were submitted to acid conditions (pH 2.4) and extremes of temperature (2 hours of sterilisation at 121 °C; freezing at -20°C). The syneresis and viscosity of the gels obtained have been compared with those obtained from commonly-used starches such as maize, waxy maize, potato and rice. Yam and yam bean starches manifested greater heat-stability than maize starch.Cassava and arracacha starch gels appeared to be the two most resistant to freezing among the 12 starches tested. Cassava and arracacha starches gave no indication of syneresis and their viscosity was unaffected under acid conditions, even after more than eight weeks of storage.This study has shown the great potentiel of certain root and tuber starches in their native form, to respond to the demande of industry for resistance to certain physical stresses. Cassava, arracacha, yam and Queensland arrowroot starches appear to be capable of satisfying some of these demands. The investigation of the physical properties of native starches helps identify new market opportunities for certain roots and tubers, and should encourage renewed interest in their cultivation. (Résumé d'auteur