Partial characterization of aerogels made from chayotextle and potato starch

Abstract

Starch aerogels were obtained from Chayotextle (Sechium edule) and potato (Solanum tuberosum) tubers. An hydrogel was formed by the gelatinization and gelling of a starch dispersion, subsequently, the exchange of water for acetone yields an acetogel, which is then subjected to a supercritical drying process with CO2 to obtain an aerogel. In the present work, we used an unconventional starch source, Chayotextle, and compared it with potato starch. A physicochemical and morphological analysis was carried out to evaluate the properties of the obtained aerogels (FTIR, SEM, % Moisture Content, Water Absorption Capacity, Resistant Starch Content, Oil Retention Capacity and Swelling). The results showed that a stirring speed of 800 RPM and 3 days of cooling allowed obtaining aerogels with a homogeneous porous structure. Changes in Moisture Content, solubility, Oil Retention Capacity, Water Retention Capacity and Swelling could be verified in the aerogels obtained. Chayotextle starch aerogels samples have a lower swelling factor and lower moisture absorption compared to potato starch aerogels. This can be used in certain strategic applications. The size of the granules of chayotextle starch allows for a higher content of resistant starch, which shows a greater tendency to retrograde than potato starch. Aerogels can be used for a variety of advanced food applications: from smart ingredients that control nutrient release to active compound delivery systems; from fat substitutes to new biodegradable and smart food packaging materials.