Thermal and functional properties of starch extracted from American taro and Indian shot were determined to assess their use in food products. Starch was extracted by the wet-milling method. Physicochemical composition was determined following the Association of Official Agricultural Chemists (AOAC) protocols. Total fibre was measured by the Total Dietary Fiber Assay Kit. The morphology of starch granules was observed by scanning electronic microscopy (SEM). Gelatinization temperature and viscosity were measured by Differential Scanning Calorimetry (DSC) and with a rapid viscosity analyser (RVA), respectively. Swelling capacity, solubility index, and absorption index were measured at 15, 60, 70, 80, and 90 °C. The yield for Indian shot (72.5 %) was higher of that for taro (60.2 %). No significant differences (p > 0.05) were found for moisture, ashes, total fibres, and protein; significant differences were found for fat content, total carbohydrates, amylose, and amylopectin. Granules of Indian shot starch featured ovoid shapes (diameter, 30 µm), while granules of American taro starch presented round shapes (diameter, 15 µm. Gelatinization temperature for American taro (78.33 °C) was higher of that for Indian shot (65.28 °C). Maximum viscosity in Indian shot (3,535.5 cP) was higher of that in American taro (2,446.5 cP). Concerning functional properties, Indian shot starch yielded higher values. Moreover, at high temperature values, American taro starch presented better gelling results than those in Indian shot.

La investigación tuvo como objetivo principal determinar la ecuación modelo operacional aplicando el principio de balance de materia en estado no estacionario. Para la representación del proceso se utilizó un tanque con agua el cual simulada el caudal de entrada al tanque que contenía una solución concentrada de 33° Brix, y de este se desprendía un caudal de salida a un tercer tanque. Las muestras se recolectaron del caudal de salida del segundo tanque en un rango de tiempo de 30 segundos, obteniendo un total de 20 muestras, luego se evaluó su concentración en °Brix analizando en el laboratorio. En la parte operacional se aplica un balance de materia en estado estacionario donde se determinó la ecuación modelo donde al aplicar el tiempo en el cual se recolecto la muestra se determinaba su concentración en °Brix. Se analizó los datos arrojados por análisis de laboratorio y los obtenidos por aplicación de la ecuación modelo en el programa estadístico Statgraphics Centurion XVI.I, el cual determino que no existió diferencia significativa entre cada uno de los datos estudiados. La ecuación modelo establecida  para determinación de la concentración de una sustancia resulto útil en al investigación y  para su aplicación en futuros estudios. AbstractThe aim of the present research work was to determine mathematical model of the operational equation applying non-stationary state material balance principle. A tank filled with water was used for the representation of the mechanical process, which simulated an input flow to a tank containing a 33° Brix sucrose concentrated solution, from where an output flow to a third tank was released. The samples were collected from the second tank output flow in time ranges of thirty seconds; a total number of twenty samples were obtained. For each sample, concentration in means of °Brix, was registered in laboratory facilities. In the operational part of the present research, a material balance in non-stationary state was utilized. The model equation for the previously mentioned state, where applying time when a sample was collected and its concentration by means of °Brix, was determined. Obtained data from laboratory analysis and from the model equation application were analyzed with statistical package Statgraphics Centurion XVI.I version XVI 16.1.18. For each data set compared, no significant differences were found. The established model equation for the determination of the concentration of a substance was useful in this investigation and it can be used in further research works.