Antifungal Soybean Protein Concentrate Adhesive as Binder of Rice Husk Particleboards

LARREGLE, A.; CHALAPUD, M.; FANGIO, F.; CIANNAMEA, E. M.; STEFANI, P.M.; MARTUCCI, J. F.; RUSECKAITE, R.A.

Polymers

Mdpi

Año: 2021 vol. 13 p. 3540 - 3541

2073-4360

Abstract: The aim of this research was to prepare an antifungal soybean protein concentrate (SPC)adhesive containing carvacrol (CRV) as a bioactive agent able to delay the attack of molds and yeastduring storage of SPC adhesive at 4 C as water-based systems. CRV was incorporated in SPC slurryat 0.5% v/v (~10 times its minimum inhibitory concentration against Aspergillus terreus, used asmodel fungus), to ensure its long-term action. CRV scarcely altered the thermal properties, structureand apparent viscosity of SPC adhesive. Active SPC aqueous dispersion was microbiologically stablefor at least 30 days at 4 C where the colonization begins, while control SPC was visually colonizedfrom the second day. Rice husk (RH) particleboards of density ~900 kg/m3 were manufacturedusing the active SPC stored for 0, 10, 20, and 30 days as a binder. Modulus of elasticity, modulus ofrupture and internal bond of RH?control SPC (without CRV) panels were 12.3 MPa, 2.65 GPa and0.27 MPa, respectively, and were statistically unaltered compared with those obtained with freshSPC, regardless of the presence of CRV or the storage time. This last implies that active SPC shouldnot necessarily have to be prepared daily and/or be used immediately after its preparation. Since itis microbiologically stabilized, it can be store at least for 30 days, ensuring the stability of the protein.The quality of the adhesive was evidenced by the consistent properties of the adhesive, expanding itspotential use and commercialization