Influence of grape treatment on the wine yeast populations isolated from spontaneous fermentations.
OBJECTIVE
To study the influence of different methods of grape treatment in wineries on the diversity of the yeast species in spontaneous fermentations.


RESULTS
Grapes were crushed and pressed in three different ways followed by spontaneous fermentation. The same grape material picked and crushed aseptically directly in the vineyard served as control. Yeasts isolated at different stages of the fermentation were characterized by 5.8S-ITS-RFLP. Yeasts of the Saccharomyces sensu stricto complex were additionally analysed by microsatellite polymerase chain reaction fingerprinting. The diversity of yeast species isolated from winery fermentations was much greater than from the vineyard fermentation in respect to yeasts of the genus Saccharomyces as well as non-Saccharomyces.


CONCLUSIONS
Oenonogical methods alter significantly the yeast diversity in spontaneous fermentations of grape juice.


CONCLUSIONS
Managing spontaneous fermentations successfully depends not only on choosing the suitable grapes but also on the crushing and pressing techniques leading to different yeast populations.
Sturm
J
J
Institut für Angewandte Mikrobiologie, Justus-Liebig Universität Giessen, Giessen, Germany.
Grossmann
M
M
Schnell
S
S
D005285:Fermentation; D014644:Genetic Variation; D007218:Industrial Microbiology; D007221:Industry; D018895:Microsatellite Repeats; D027843:Vitis / Q000382:microbiology*; D014920:Wine / Q000382:microbiology*; D015003:Yeasts / Q000235:genetics* / Q000502:physiology