title: Stillage reflux in food waste ethanol fermentation and its by-product accumulation.
abstract: Raw materials and pollution control are key issues for the ethanol fermentation industry. To address these concerns, food waste was selected as fermentation substrate, and stillage reflux was carried out in this study. Reflux was used seven times during fermentation. Corresponding ethanol and reducing sugar were detected. Accumulation of by-products, such as organic acid, sodium chloride, and glycerol, was investigated. Lactic acid was observed to accumulate up to 120g/L, and sodium chloride reached 0.14mol/L. Other by-products did not accumulate. The first five cycles of reflux increased ethanol concentration, which prolonged fermentation time. Further increases in reflux time negatively influenced ethanol fermentation. Single-factor analysis with lactic acid and sodium chloride demonstrated that both factors affected ethanol fermentation, but lactic acid induced more effects.
authors.affiliation: Department of Environmental Engineering, University of Science and Technology, Beijing 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, Beijing, China.
authors.forename: Hongzhi
authors.initials: H
authors.lastname: Ma
authors.affiliation: Department of Environmental Engineering, University of Science and Technology, Beijing 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, Beijing, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Environmental Engineering, University of Science and Technology, Beijing 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, Beijing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Jia
authors.affiliation: Department of Environmental Engineering, University of Science and Technology, Beijing 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, Beijing, China.
authors.forename: Qunhui
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Tashiro
authors.affiliation: Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Sonomoto
mesh_terms: D002241:Carbohydrates / Q000032:analysis; D002264:Carboxylic Acids / Q000032:analysis; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D005502:Food; D005990:Glycerol / Q000032:analysis; D019344:Lactic Acid / Q000378:metabolism; D009930:Organic Chemicals / Q000032:analysis; D012965:Sodium Chloride / Q000378:metabolism; D014866:Waste Products / Q000032:analysis*
chemical_list: D002241:Carbohydrates; D002264:Carboxylic Acids; D009930:Organic Chemicals; D014866:Waste Products; D019344:Lactic Acid; D000431:Ethanol; D012965:Sodium Chloride; D005990:Glycerol
keywords: Ethanol fermentation; Food waste; Stillage reflux