Morphological properties of “Regalona” Quinoa and its adsorption isotherm modeling

Contreras-López E.; Cañumir-Veas J.A.; Vidal-Jiménez L.; Muñoz A.M.; Gonzalez M.E. · Revue des Etudes Slaves (2026) · DOI: 10.15446/rfnam.v79.124831

Resumen

“Regalona” quinoa, the only commercial variety cultivated in Chile, is a coastal ecotype developed from the genetic material, traditionally harvested by Mapuche women in the Araucania region. This study determined the moisture sorption isotherms of “Regalona” quinoa at 20, 30 and 40 °C using six mathematical models (GAB, BET, Smith, Halsey, Oswin, and Henderson), and estimated isosteric heat of sorption, water adsorption surface area and grain morphology. Equilibrium moisture content was determined using the static gravimetric method. Among the evaluated models, GAB provided the best overall fit, followed by Henderson and Oswin. The monolayer moisture content, estimated from the GAB model, ranged from 6.97 to 11.55 g H₂O per 100 g of solids, depending on temperature. The net isosteric heat of sorption was 6.26 kJ mol-1 at a moisture content of 5.0%, and the water adsorption surface area ranged from 247.28 to 409.60 m² g-1 depending on temperature. These findings indicate that the hygroscopic behavior of “Regalona” quinoa is influenced by its compositional and structural characteristics and provide a basis for estimating critical moisture contents and optimizing drying processes.

Instituciones: Universidad Nacional Mayor de San Marcos; Universidad San Ignacio de Loyola