title: Grain sorghum is a viable feedstock for ethanol production.
abstract: Sorghum is a major cereal crop in the USA. However, sorghum has been underutilized as a renewable feedstock for bioenergy. The goal of this research was to improve the bioconversion efficiency for biofuels and biobased products from processed sorghum. The main focus was to understand the relationship among "genetics-structure-function-conversion" and the key factors impacting ethanol production, as well as to develop an energy life cycle analysis model (ELCAM) to quantify and prioritize the saving potential from factors identified in this research. Genetic lines with extremely high and low ethanol fermentation efficiency and some specific attributes that may be manipulated to improve the bioconversion rate of sorghum were identified. In general, ethanol yield increased as starch content increased. However, no linear relationship between starch content and fermentation efficiency was found. Key factors affecting the ethanol fermentation efficiency of sorghum include protein digestibility, level of extractable proteins, protein and starch interaction, mash viscosity, amount of phenolic compounds, ratio of amylose to amylopectin, and formation of amylose-lipid complexes in the mash. A platform ELCAM with a base case showed a positive net energy value (NEV) = 25,500 Btu/gal EtOH. ELCAM cases were used to identify factors that most impact sorghum use. For example, a yield increase of 40 bu/ac resulted in NEV increasing from 7 million to 12 million Btu/ac. An 8% increase in starch provided an incremental 1.2 million Btu/ac.
authors.affiliation: Department of Biological and Agricultural Engineering, Kansas State University, Manhattan, KS, 66506, USA. dwang@ksu.edu.
authors.forename: D
authors.initials: D
authors.lastname: Wang
authors.affiliation: USDA-ARS Grain Marketing and Production Research Center, Manhattan, KS, 66502, USA.
authors.forename: S
authors.initials: S
authors.lastname: Bean
authors.affiliation: StrathKirn Inc, Chesterfield, MO, 63017, USA.
authors.forename: J
authors.initials: J
authors.lastname: McLaren
authors.affiliation: Department of Grain Science and Industry, Kansas State University, Manhattan, KS, 66506, USA.
authors.forename: P
authors.initials: P
authors.lastname: Seib
authors.affiliation: Department of Grain Science and Industry, Kansas State University, Manhattan, KS, 66506, USA.
authors.forename: R
authors.initials: R
authors.lastname: Madl
authors.affiliation: Department of Agronomy, Kansas State University, Manhattan, KS, 66506, USA.
authors.forename: M
authors.initials: M
authors.lastname: Tuinstra
authors.affiliation: Department of Grain Science and Industry, Kansas State University, Manhattan, KS, 66506, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Monsanto, 7159 N. 247th West, Mt Hope, KS, 67108, USA.
authors.forename: M
authors.initials: M
authors.lastname: Lenz
authors.affiliation: Department of Biological and Agricultural Engineering, Kansas State University, Manhattan, KS, 66506, USA.
authors.forename: X
authors.initials: X
authors.lastname: Wu
authors.affiliation: Department of Biological and Agricultural Engineering, Kansas State University, Manhattan, KS, 66506, USA.
authors.forename: R
authors.initials: R
authors.lastname: Zhao
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D001674:Bioelectric Energy Sources; D001711:Biotransformation; D004736:Energy-Generating Resources; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D006868:Hydrolysis; D008954:Models, Biological; D045868:Sorghum / Q000737:chemistry / Q000166:cytology / Q000378:metabolism*; D013213:Starch / Q000737:chemistry / Q000378:metabolism; D014783:Viscosity
chemical_list: D000431:Ethanol; D013213:Starch