title: Storage of immobilized yeast cells for use in wine-making at ambient temperature.
abstract: A comparative study of the storage and reuse of immobilized yeast cells on apple pieces, kissiris, and gamma-alumina was carried out. The immobilized biocatalysts were allowed to remain in the fermented alcoholic liquid after the end of each fermentation batch for extended periods at 30 degrees C before reactivation in batch fermentation for wine-making. The results showed that the biocatalysts were able to reactivate and ferment after successively increased periods of storage compared to free cell systems both on glucose medium and on grape must. In glucose medium, apple-, kissiris-, and gamma-alumina-supported biocatalysts reactivated after 120, 80, and 83 days, respectively. Possible storage periods for grape must were lower but remained high. Immobilized yeast biocatalyst on apple pieces produced wines with an improved volatiles composition compared to kissiris- and gamma-alumina-supported biocatalysts. There were no significant negative effects on the fermentation activity and volatile byproduct composition.
authors.affiliation: Food Biotechnology Group, Department of Chemistry, Section of Analytical, Environmental and Applied Chemistry, University of Patras, GR-26500 Patras, Greece.
authors.forename: Yiannis
authors.initials: Y
authors.lastname: Kourkoutas
authors.forename: Maria
authors.initials: M
authors.lastname: Kanellaki
authors.forename: Athanasios A
authors.initials: AA
authors.lastname: Koutinas
authors.forename: Ibrahim M
authors.initials: IM
authors.lastname: Banat
authors.forename: Roger
authors.initials: R
authors.lastname: Marchant
mesh_terms: D000537:Aluminum Oxide; D018914:Cells, Immobilized / Q000502:physiology*; D003362:Cost-Benefit Analysis; D005285:Fermentation; D005524:Food Technology / Q000191:economics / Q000379:methods*; D005947:Glucose; D027845:Malus; D012441:Saccharomyces cerevisiae / Q000502:physiology*; D013997:Time Factors; D014835:Volatilization; D014920:Wine
chemical_list: D005947:Glucose; D000537:Aluminum Oxide