La jícama (Pachyrhizus erosus L.) pertenece a la familia de las leguminosas y al género Pachyrhizus; el órgano estructural comestible de esta planta es la raíz; se consume en fresco, tiene bajo contenido calórico (40 cal), vitaminas, minerales y carbohidratos como el almidón; este es único entre los carbohidratos que se producen en la naturaleza en forma de gránulos intracelulares; se reconoce la importancia que tiene la organización física de estos gránulos en su funcionalidad y comportamiento de los productos alimenticios. Por ello, la presente investigación tuvo como objetivo la caracterización fisicoquímica y químico proximal de almidón y harina de jícama de las localidades de Pantanal y Camichin del estado de Nayarit generando cuatro tratamientos (T1=Pantanal Almidón, T2= Camichin Almidón, T3=Pantanal Harina y T4= Camichin Harina); se evaluaron las variables de pH, acidez titulable, densidad aparente, color,humedad, cenizas, proteínas, lípidos, amilosa, amilopectina, fibra total y carbohidratos totales. El almidón del T2 presento los valores más altos de cenizas (2.44%), fibra (170 mg/100g) y carbohidratos (1.50 g), de igual forma la harina de del T4 presento los valoresaltos de cenizas (3.55%), proteínas (11.04%), fibra (181 mg/100g) y de carbohidratos (1.70 g). Estas características los hacen viables tanto para la sustitución parcial o total de almidones y harinas comerciales, como en la producción de diferentes alimentos a base de estos.

Starch is one of the most used polysaccharides in the food industry because is an excellent raw material to modify the texture and consistency of food. Also, is the main source for energy storage in horticultural products. The starch from soursop fruits can be used as an alternative source with functional properties and a wide field of application in the food industry. The use of emerging technologies such as ultrasound-assisted extraction has improved sensory attributes and functional properties. To the best of our knowledge, extraction of starch by ultrasound from soursop fruits has not to date been documented. Therefore, the objective of this study was to characterize the functional properties of soursop fruit starches by ultrasound-assisted method and determine the presence of acetogenins. Three times (10, 15 and 20 minutes) and three ultrasonic amplitudes (UA) of 20, 30 and 40% for the ultrasound-assisted extraction were used. Total yield, gelatinization temperature, water absorption and solubility index, swelling index, amylose and amylopectin content, presence of acetogenins and starch granule morphology were recorded. The highest extraction yield (ultrasound) was reached using 10 min and 40% UA (6.34%). For the gelatinization temperature, 10 min and 30% UA (82.33°C) were the best conditions. Water Solubility Index (WSI) values of 6.13 ± 0.00% using 10 min and 20% UA were recorded. Water Absorption Index (WAI) as well as Swelling index (SI) values of 3.34 ± 0.12% and 3.26 ± 0.00% were obtained by conventional extraction, respectively. Starch granules morphology showed different size with circular shapes and truncated geometries. Finally, positive qualitative results for the presence of acetogenins by all the extraction methods were obtained.