Related Experiment Video
Updated: Oct 15, 2026
In vitro Digestion of Emulsions in a Single Droplet via Multi Subphase Exchange of Simulated Gastrointestinal Fluids
Published on: November 18, 2022
pH-shifting and high-intensity ultrasound enable the functional design of quinoa protein isolate as a plant-based
Vilbett Briones-Labarca1, Claudia Giovagnoli-Vicuña2, María José Bugueño1
1Departamento de Ingeniería en Alimentos, Universidad de La Serena, Av. Raúl Bitrán Nachary 1305, Box 599, La Serena, 1720010, Chile.
Abstract:
Quinoa protein isolate (QPI) derived from dehulling by-products was structurally tailored using a combined pH-shifting and high-intensity ultrasound (HIU) approach to enhance its functionality as a plant-based emulsifier. Alkaline conditions (pH 11) promoted protein unfolding, increasing solubility, surface charge, and exposure of reactive groups, including higher free sulfhydryl content and oil-holding capacity. These changes improved interfacial activity and emulsifying performance. A Box-Behnken design optimized HIU conditions and formulation variables, producing emulsions with minimal phase separation (SI ≈ 0%), small droplet size (0.35 ± 0.02 μm), and dominant elastic behavior (G' > G″). The optimized system also showed high thermal stability (98% at 80 °C). These findings demonstrate that pH-induced structural modification combined with ultrasound enables the functional design of QPI as an effective emulsifier and highlights quinoa by-products as sustainable sources of clean-label ingredients.
