Abstract

This paper presents the absorption, mechanical, and antimicrobial properties of novel types of biofoams based on wheat-gluten (WG) and its biohybrids with silica. The hybrid WG foams were in situ polymerized with silica using two different silanes. When immersed in water, the 90-95% porous WG and silica-modified hybrid WG foams showed a maximum water uptake between 32 and 11 times the original sample weight. The maximum uptake was only between 4.3 and 6.7 times the initial weight in limonene (a nonpolar liquid) but showed reversible absorption/desorption and that the foams could be dried into their original shape. The different foams had a cell size of 2-400 mu m, a density of 60-163 kg/m(3), and a compression modulus of 1-9 MPa. The integrity of the foams during swelling in water was improved by cross-linking with glutaraldehyde (GA) or by a thermal treatment at 130 degrees C, which polymerized the proteins. In the never-dried state, the foam acted as a sponge, and it was possible to squeeze out water and soak it repeatedly. If the foam was dried to its glassy state, then the cells collapsed and did not open again even if the solid foam was reimmersed in water, saving as a sensor mechanism that can be used to reveal unintended exposure to polar liquids such as water under a product's service life. Small-angle X-ray scattering revealed that the gliadin-correlated structure expanded and then disappeared in the presence of water. The foam was made antimicrobial by impregnation with a Lanasol solution (a bromophenol existing in algae). It was also shown that the foam can act as a transfer/storage medium for liquids such as natural oils (rapeseed oil) and as a slow-release matrix for surfactant chemicals.

Keywords

Protein; Freeze-drying; Swelling; Sponge; Lanasol

Published in

ACS Sustainable Chemistry and Engineering
2016, Volume: 4, number: 4, pages: 2395-2404
Publisher: AMER CHEMICAL SOC

SLU Authors

• Johansson, Eva

  • Department of Plant Breeding, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Other Materials Engineering


Publication identifier

DOI: https://doi.org/10.1021/acssuschemeng.6b00099

Permanent link to this page (URI)

https://res.slu.se/id/publ/80926