Comparative study of four extraction methods of fructans (agavins) from Agave durangensis: Heat treatment, ultrasound, microwave and simultaneous ultrasound-microwave.

Agavins (fructans from the agave plant) are used for their technological and prebiotic properties in developing functional foods. In this study, four extraction methods were evaluated: ultrasound (U), microwave (M), simultaneous ultrasound-microwave (UM), and heat treatment (HT). Isomers with a degree of polymerization (DP) > 10, as well as a significant concentration of fructooligosaccharides (FOS) were identified. The yield obtained by UM (72%) was similar to the other methods; however, the extraction time was shorter (5 min). In U, M, and HT the yields were 86, 76, and 85% in 35, 30, and 180 min, respectively. In addition, FTIR spectra showed evidence of regions corresponding to fatty acids and carbohydrates. Therefore, using UM to obtain agavins is a more ecological and faster process.