Freeze-dried Saccharomyces cerevisiae cells immobilized on potato pieces for low-temperature winemaking.
A biocatalyst was prepared by immobilization of Saccharomyces cerevisiae AXAZ-1 yeast cells on potato pieces. This biocatalyst was subjected to freeze-drying, and the effect of several protective agents and storage at 5 °C, up to 9 months, on viability and fermentative activity of yeasts cells were studied. From several protective agents tested, sodium glutamate preserved the viability of immobilized yeast cells at high levels even after 9-month storage. The freeze-drying biocatalyst was used for repeated batch fermentations of grape must at low temperatures until 5 °C. The produced wines analyzed for volatile byproducts by GC and GC/MS and the results showed that the freeze-dried biocatalysts, with sodium glutamate as protectant, produced wines with higher formation of esters than free cells and having at least similar aromatic profile to those produced by wet biocatalysts.
Food Biotechnology Group, Department of Chemistry, University of Patras, GR-26500, Patras, Greece, pkandylis@yahoo.gr.
Panagiotis
P
Kandylis
Dimitra
D
Dimitrellou
Paraskevi
P
Lymnaiou
Athanasios A
AA
Koutinas
D018914:Cells, Immobilized / Q000378:metabolism; D005612:Freeze Drying; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D011198:Solanum tuberosum; D014920:Wine