Effect of the retrogradation time on the morphological properties of vacuum-dried chayotextle (Sechium edule) and potato (Solanum tuberosum) starch aerogels

This study is focused on the production of starch aerogels from two different tubers (potato and chayotextle), using the vacuum drying technique, evaluating different retrogradation times and their effect on the morphology and pore size of the produced aerogels. The gels obtained presented a rigid and rough structure in the form of a monolith, with a high degree of contraction after the applied drying. Samples were analyzed by FT-IR, SEM, and the measurements of porosity and density. The FTIR analysis revealed characteristic signals of starch and structural changes as the retrogradation time increased from 3 to 6 days. This could be related to the generation of helical structures during starch reorganization. The structure of the obtained aerogels is openly porous, and uniform. Samples with longer retrogradation time have lower porosity, higher density, and greater size distribution, with small-sized pores less than 0.5 µm and macropores greater than 2 µm.