title: Incorporation of whey permeate, a dairy effluent, in ethanol fermentation to provide a zero waste solution for the dairy industry.
abstract: This study proposes a novel alternative for utilization of whey permeate, a by-product stream from the dairy industry, in wheat fermentation for ethanol production using Saccharomyces cerevisiae. Whey permeates were hydrolyzed using enzymes to release fermentable sugars. Hydrolyzed whey permeates were integrated into wheat fermentation as a co-substrate or to partially replace process water. Cold starch hydrolysis-based simultaneous saccharification and fermentation was done as per the current industrial protocol for commercial wheat-to-ethanol production. Ethanol production was not affected; ethanol yield efficiency did not change when up to 10% of process water was replaced. Lactic acid bacteria in whey permeate did not negatively affect the co-fermentation or reduce ethanol yield. Whey permeate could be effectively stored for up to 4 wk at 4 °C with little change in lactose and lactic acid content. Considering the global abundance and nutrient value of whey permeate, the proposed strategy could improve economics of the dairy and biofuel sectors, and reduce environmental pollution. Furthermore, our research may be applied to fermentation strategies designed to produce value-added products other than ethanol.
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, T6G 2P5, Canada.
authors.forename: Archana
authors.initials: A
authors.lastname: Parashar
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, T6G 2P5, Canada.
authors.forename: Yiqiong
authors.initials: Y
authors.lastname: Jin
authors.affiliation: Verschuren Centre for Sustainability in Energy & the Environment, Cape Breton University, Sydney, B1P 6L2, Nova Scotia, Canada.
authors.forename: Beth
authors.initials: B
authors.lastname: Mason
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, T6G 2P5, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Chae
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, T6G 2P5, Canada. Electronic address: david.bressler@ualberta.ca.
authors.forename: David C
authors.initials: DC
authors.lastname: Bressler
mesh_terms: D000818:Animals; D056804:Biofuels; D002417:Cattle; D003612:Dairying / Q000379:methods*; D004787:Environmental Pollution / Q000517:prevention & control; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D006868:Hydrolysis; D007220:Industrial Waste / Q000032:analysis*; D007785:Lactose / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D012996:Solutions; D000067796:Whey / Q000737:chemistry*
chemical_list: D056804:Biofuels; D007220:Industrial Waste; D012996:Solutions; D000431:Ethanol; D007785:Lactose
keywords: Saccharomyces cerevisiae; cheese whey; dairy by-product; ethanol fermentation; whey permeate