Bio-catalytic action of twin-screw extruder enzymatic hydrolysis on the deconstruction of annual plant material: Case of sweet corn co-products

• Published in: Industrial crops and products Vol. 67; pp. 239 - 248
• Main Authors: Vandenbossche, Virginie, Brault, Julien, Vilarem, Gérard, Rigal, Luc
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.05.2015; Elsevier
• Subjects: Alkaline pre-treatment; Bioextrusion; Catalysis; Chemical and Process Engineering; Chemical Sciences; Corn; Engineering Sciences; Enzymatic hydrolysis; Enzymes; Fibers; Food engineering; Life Sciences; Mathematical models; Pretreatment; Sugars; Sweet corn co-product; Sweets; Twin screw extruders; Twin-screw extruder; Bioextrusion; Alkaline pre-treatment; Sweet corn co-product; Enzymatic hydrolysis; Twin-screw extruder
• ISSN: 0926-6690; 1872-633X
• DOI: 10.1016/j.indcrop.2015.01.041

•Process combines thermo-mechano-chemical and the bio-catalytic action in extruder.•Sweet corn co-products serve as a biomass model.•Impact of biocatalytic action on deconstruction of lignocellulosic biomass is studied.•Saccharification begins during bioextrusion.•Hydrolytic enzymes are not deactivated during bioextrusion. A continuous process combining an alkaline thermo-mechano-chemical pretreatment neutralization step, followed by injection of enzymes into the twin-screw extruder, was developed using sweet corn co-products as a biomass model. The implementation of the continuous process is described. Particular attention is paid to the influence of the bio-catalytic action of enzymatic hydrolysis on the deconstruction of annual plant material in the twin-screw extruder (a process called “bioextrusion”). The use of a twin-screw extruder allows working with high consistency (20%), in a high shear environment, for a short time (∼2min). In the present work, the nature of the ligno(hemi)cellulosic material transformations, covering solubilization and extraction of saccharides and modification of cellulosic fibers, were investigated. 41% of hemicelluloses and 14% of lignin are extracted by the alkaline pretreatment. Hydrolytic enzymes are not deactivated during bioextrusion, which has a destructing effect on the fiber. It leads to a change of rheological properties and induces an increase of sugars released in the form of mono and polysaccharides (up to 13%/DM of total sugars) with longer chains than in the case of a batch reactor. At the same time, the degree of polymerization decreases and a shortening of the cellulose chains occurs.