Three-Dimensional Biomass Composites Using the Maillard Reaction Products of Molasses as a Binder

Abstract

Here we found that viscoelastic features of molassesfacilitate paste formation with wheat bran and rice straw powders, and a subsequentheat treatment results in significant hardening with dehydrationand the Maillard reaction. This simple two-step process (i.e., blendingand heating) was beneficial to fabricate diverse 3-dimensional shapes.The hardening process displayed around 3.5, 0.5, and 2.5 MPa as compressive, tensile, and flexural strengths, respectively, when a 1:1 (v/v) ratio of molasses and the biomasspowders was used. Instrumental analyses on molasses before and afterthe heat process and hardening with a model compound (i.e., gallicacid) revealed that structural transformations of molasses based onthe Maillard reactions and concomitant coupling reactions with ligninor polyphenolic moieties from the biomass are crucial for the phenomenon.Practical functionalities such as antibacterial, nonbiodegradable,and virus particle-adsorbing properties potentially attributable tothe lignin and melanoidin contents were also exhibited with the composites.