Assessment of the effect of autohydrolysis treatment in banana’s pseudostem pulp

• Published in: Waste management (Elmsford) 2021-01, Vol.119, p.306-314
• Main Authors: Díaz, Sara, Ortega, Zaida, Benítez, Antonio N., Costa, Diogo, Carvalheiro, Florbela, Fernandes, Maria C., Duarte, Luís C.
• Format: Article
• Language: English
• Subjects: Agricultural Wastes; Autohydrolysis; Banana wastes; Biomass pretreatment; Biorefinery; Enzymatic digestibility; Enzymatic hydrolysis; Hydrolysis; Lignin; Musa; Oligosaccharides; Polysaccharides
• ISSN: 0956-053X; 1879-2456
• DOI: 10.1016/j.wasman.2020.09.034

[Display omitted] •Autohydrolysis of post-fibre extraction pulp from banana pseudostem was studied.•A high concentration of malto-oligosaccharides was obtained in the liquors.•Solid fraction presented an improved enzymatic digestibility for further valorization.•Two-stage autohydrolysis improved oligosaccharides production and solid digestibility. Banana’s pseudostem pulp (BPP) is a potential by-product obtained in the mechanical fiber extraction of banana’s pseudostem. Its chemical characterization revealed to have an interesting composition, with a high polysaccharides content and low content in lignin, which makes it particularly relevant for the biorefinery’s biochemical platform. Autohydrolysis pretreatment, studied under isothermal (140 °C) and non-isothermal conditions (140–220 °C), yielded oligosaccharides, mainly gluco-oligosaccharides, as the main soluble products. The highest oligosaccharides production (24 g/100 g raw material) was obtained at a severity factor of 2.3. Autohydrolysis pretreatment effectively disrupted the structure of the material, inducing an improvement of the enzymatic digestibility from 73% for the raw material up to 90% for the most severe conditions. Two stage autohydrolysis, with increasing severity, was also studied, allowing to obtain a higher amount of oligosaccharides (32 g/100 g raw material) and higher digestibility of the remaining solid (up to 97%).