title: Sediments in coffee extracts: Composition and control by enzymatic hydrolysis.
abstract: The water-insolubility of some coffee extract components is one of the major limitations in the production of instant coffee. In this work, fractions from coffee extracts and sediments were prepared, and their chemical composition determined. Based on the carbohydrate analysis, galactomannan was found to be the main polysaccharide component of the insoluble fractions and probably responsible for sediment formation. The suitability of twelve commercial enzymes for the hydrolysis of the insoluble fractions was investigated. Pectinase 444L was the most effective enzyme in releasing sugars, mainly mannose and galactose, from these substrates. Biopectinase CCM, Rohapect B1L, Pectinase 444L and Galactomannanase ACH were found to be the most effective enzymes for reducing the sediment of coffee extracts. The highest sediment reduction was obtained using Rohapect B1L and Galactomannanase ACH, at enzyme concentrations of 0.3 and 0.1mg protein/g substrate, respectively.
authors.affiliation: School of Chemical Engineering, State University of Campinas, UNICAMP, P.O. Box 6066, 13081-970 Campinas, SP, Brazil.
authors.forename: P A
authors.initials: PA
authors.lastname: Delgado
authors.affiliation: Cia. Iguaçu de Café Solúvel, BR 369, Km 88, 86300-000 Cornélio Procópio, PR, Brazil.
authors.forename: J A
authors.initials: JA
authors.lastname: Vignoli
authors.affiliation: VTT Biotechnology, FIN-0204, P.O. Box 1500, Espoo, Finland.
authors.forename: M
authors.initials: M
authors.lastname: Siika-Aho
authors.affiliation: School of Chemical Engineering, State University of Campinas, UNICAMP, P.O. Box 6066, 13081-970 Campinas, SP, Brazil. Electronic address: franco@feq.unicamp.br.
authors.forename: T T
authors.initials: TT
authors.lastname: Franco
keywords: Coffee composition; Coffee polysaccharides; Enzymatic hydrolysis; Galactomannans; Instant coffee; Sediment