title: Use of different extracts of coffee pulp for the production of bioethanol.
abstract: Coffee is one of the most important agricultural products in Brazil. More than 50 % of the coffee fruit is not used for the production of commercial green coffee and is therefore discarded, usually ending up in the environment. The goal of this work was to select an efficient process for obtaining coffee pulp extract and to evaluate the use of this extract in bioethanol production. The effects of heat treatment and trituration on the yield and composition of the extract were investigated by measuring the amounts of reducing sugars, starch, pectin, and phenolic compounds. The extraction process was most efficient at room temperature using grinding followed by pressing. Five different fermentation media were tested: sugarcane juice or molasses diluted with water or with coffee pulp extract and a medium with only coffee pulp extract. Batch fermentations were carried out at 30 °C for 24 h, and samples were taken to obtain measurements of the total reducing sugars, cell count, and ethanol concentration. The addition of coffee pulp extract did not influence the fermentation or yeast viability, and it can thus be mixed with sugarcane juice or molasses for the production of bioethanol, with a yield of approximately 70 g/L.
authors.affiliation: Departamento de Ciência dos Alimentos, Universidade Federal de Lavras, Lavras, MG, Brazil. evandrogtmenezes@gmail.com
authors.forename: Evandro Galvão Tavares
authors.initials: EG
authors.lastname: Menezes
authors.forename: Juliana Ribeiro
authors.initials: JR
authors.lastname: do Carmo
authors.forename: Aline Galvão Tavares
authors.initials: AG
authors.lastname: Menezes
authors.forename: José Guilherme Lembi Ferreira
authors.initials: JG
authors.lastname: Alves
authors.forename: Carlos José
authors.initials: CJ
authors.lastname: Pimenta
authors.forename: Fabiana
authors.initials: F
authors.lastname: Queiroz
mesh_terms: D056804:Biofuels / Q000382:microbiology*; D040503:Coffea / Q000737:chemistry / Q000382:microbiology*; D000431:Ethanol / Q000302:isolation & purification* / Q000378:metabolism*; D010936:Plant Extracts / Q000737:chemistry / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*
chemical_list: D056804:Biofuels; D010936:Plant Extracts; D000431:Ethanol