Article Dans Une Revue Food Hydrocolloids Année : 2025

Upcycling stale bread into (meso)porous materials: Xerogels and aerogels

Résumé

This work explores the upcycling of stale bread into bio-based, low-density porous materials with partial mesoporosity, produced through gelatinization and drying, using either supercritical CO 2 (aerogels) or low-vacuum conditions (xerogels). Cryogels were also fabricated via freeze-drying for comparison purposes. Stale bread particles (Bread) were subjected to proteolytic gluten depletion (Gluten-Depleted Bread, GDB) or particle size reduction (Finely milled Bread, FB) to investigate the effect of protein removal or particle size on porous materials' properties. Porous materials made from wheat starch (WS) and wheat flour (Flour) were also examined for comparison. The solvent exchange induced volume shrinkage (SE-VS), which accounted for over 87% of the total shrinkage, ranged from 62% in GDB to 78% in WS. Bread-based porous materials presented comparable specific surface area (~40 m 2 /g) and water absorption capacity (~400%) to WS materials, but outperformed in resistance to volume shrinkage, resulting in lower density. FB porous materials possessed a higher specific surface area than Bread materials, indicating the benefits of particle size reduction. Furthermore, gluten depletion resulted in GDB-aerogels with the highest specific surface area (~80 m 2 /g), highlighting the benefits of gluten depletion. However, WS materials exhibited significantly greater maximum compressive stress (>2.0 MPa) and compressive modulus (>6 MPa) than stale bread-based porous materials. Importantly, the porous properties of xerogels and aerogels were similar (differences < 10%), indicating the feasibility of using low vacuum drying to produce new porous materials with partial mesoporosity (surface area 60-80 m 2 /g) from stale bread at a lower cost.
Fichier principal
Vignette du fichier
Upcycling stale bread into (meso)porous materials Xerogels and aerogels.pdf (8.72 Mo) Télécharger le fichier
Origine Publication financée par une institution
licence

Dates et versions

hal-04876642 , version 1 (09-01-2025)

Licence

Identifiants

Citer

Wanxiang Guo, Tatiana Budtova, Mario M Martinez. Upcycling stale bread into (meso)porous materials: Xerogels and aerogels. Food Hydrocolloids, 2025, 160 (1), pp.110807. ⟨10.1016/j.foodhyd.2024.110807⟩. ⟨hal-04876642⟩
0 Consultations
0 Téléchargements

Altmetric

Partager

More