Ensiling as biological pretreatment of grass (Festulolium Hykor): The effect of composition, dry matter, and inocula on cellulose convertibility

• Published in: Biomass & bioenergy 2013-11, Vol.58, p.303-312
• Main Authors: Ambye-Jensen, Morten, Johansen, Katja S., Didion, Thomas, Kádár, Zsofiá, Schmidt, Jens E., Meyer, Anne S.
• Format: Article
• Language: English
• Subjects: bioenergy; Biofuel production; Biological and medical sciences; biomass; Biomass characterisation; Biotechnology; cellulose; Cellulose convertibility; Energy; Ensiling; Enzymatic hydrolysis; Festulolium; fuel production; Fundamental and applied biological sciences. Psychology; Grass; grasses; growing season; hydrolysis; Industrial applications and implications. Economical aspects; lactic acid; lactic acid bacteria; lignocellulose; silage making
• ISSN: 0961-9534; 1873-2909
• DOI: 10.1016/j.biombioe.2013.08.015

Grass biomass is a prospective type of lignocellulosic biomass for bioenergy and fuel production, but the low dry matter in grass at harvest calls for new pretreatment strategies for cellulosic conversion. In this study, ensiling was tested as a biological pretreatment method of the high yielding grass variety Festulolium Hykor. The biomass was harvested in four cuts over a growing season. Three important factors of ensiling: biomass composition, dry matter (DM) at ensiling, and inoculation of lactic acid bacteria, were assessed in relation to subsequent enzymatic cellulose hydrolysis. The organic acid profile after ensiling was dependant on the composition of the grass and the DM, rather than on the inocula. High levels of organic acids, notably lactic acid, produced during ensiling improved enzymatic cellulose convertibility in the grass biomass. Ensiling of less mature grass gave higher convertibility. Low DM at ensiling (