Effects of multiscale-mechanical fragmentation on techno-functional properties of industrial tobacco waste

Tobacco waste is rich in bioactive ingredients, and fragmentation is essential for its utilization. Tobacco leaf and stem at the organ (-mm), tissue (500-100 mu m), and cell (50-10 mu m) scales were prepared using sieve-based grinding and ball milling. Effects of plant scale on physicochemical, structural, and antioxidant properties were investigated. Ball milling produced cell-scale particles with a median particle size of similar to 10 mu m, and microstructure showed spherical particles and strip-shaped fibers for leaf and stem, respectively. Decreasing scale resulted in worse flowability, and cell-scale particles exhibited enhancements considerably in cell wall breakage, brightness, and yellowness. Fourier transform infrared spectra confirmed the unaltered primary structure, while blue shift for cell-scale samples suggested the breakage of linkages in polysaccharides. Three endothermic peaks were found from thermodynamic curves at 20-320 degrees C. The yields of polyphenols, nicotine, and antioxidant ability were higher in tissue-and cell-scale particles. Overall, the leaf possessed higher color values, hydration capacity, and functionality but lower density than the stem. This study showed that tobacco leaf owned higher utilization potential than stem in functional properties. (c) 2022 Published by Elsevier B.V.