title: Immobilization of Oenococcus oeni in lentikats® to develop malolactic fermentation in wines.
abstract: Entrapment of Oenococcus oeni into a polymeric matrix based on polyvinyl alcohol (PVA) (Lentikats®) was successfully used to get a better development of malolactic fermentation (MLF) in wine. The incubation of immobilized cells in a nutrient medium before starting the MLF, did not improve the degradation of malic acid. In only one day, 100% of conversion of malic acid was achieved using a high concentration of immobilized cells (0.35 g gel/ml of wine with a cell-loading of 0.25 mg cells/mg of gel). While a low concentration of 0.21 g gel/ml of wine (cell-loading of 0.25 mg cells/mg of gel) needed 3 days to get a reduction of 40%. The entrapped cells could be reused through six cycles (runs of 3 days), retaining 75% of efficacy for the conversion of malic acid into lactic acid. The immobilized cells in PVA hydrogels gave better performance than free cells because of the increase of the alcohol toleration. Consequently, the inhibitory effect of ethanol for developing MLF could be reduced using immobilized cells into PVA hydrogels.
authors.affiliation: Departamento de Ingeniería Agrícola y Forestal, Tecnología de los Alimentos, E.T.S. Ingenierías Agrarias, Universidad de Valladolid, 34004 Palencia, Spain. rjosem@iaf.uva.es
authors.forename: José Manuel
authors.initials: JM
authors.lastname: Rodríguez-Nogales
authors.forename: Josefina
authors.initials: J
authors.lastname: Vila-Crespo
authors.forename: Encarnación
authors.initials: E
authors.lastname: Fernández-Fernández
mesh_terms: D018914:Cells, Immobilized / Q000737:chemistry / Q000378:metabolism; D005285:Fermentation; D020100:Hydrogels / Q000737:chemistry / Q000378:metabolism; D008293:Malates / Q000378:metabolism*; D056585:Oenococcus / Q000737:chemistry / Q000166:cytology / Q000378:metabolism*; D011142:Polyvinyl Alcohol / Q000737:chemistry / Q000378:metabolism*; D014920:Wine / Q000032:analysis / Q000382:microbiology*
chemical_list: D020100:Hydrogels; D008293:Malates; D011142:Polyvinyl Alcohol