Premium
The influence of pre‐fermentative practices on the dominance of inoculated yeast starter under industrial conditions
Author(s) -
Ciani Maurizio,
Pepe Vincenzo
Publication year - 2002
Publication title -
journal of the science of food and agriculture
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.782
H-Index - 142
eISSN - 1097-0010
pISSN - 0022-5142
DOI - 10.1002/jsfa.1082
Subject(s) - starter , fermentation , yeast , saccharomyces cerevisiae , saccharomyces , biology , food science , inoculation , biochemistry , horticulture
The influence of pre‐fermentative practices on the growth dynamics of a ‘natural’ starter culture with specific phenotype (H 2 S − ) concurrently with wild yeast populations was evaluated under winery conditions. Different clarification procedures and added SO 2 strongly influenced species and cell numbers isolable at the pre‐fermentation stage. Independent treatments of must with sulphite addition or vacuum‐filtering clarification caused a 30‐fold reduction in viable cells. Clarification procedures, enhanced by the selective effect of SO 2 addition, induced the appearance of Saccharomyces cerevisiae ‘wild’ yeasts. Correct application of the inoculum generally guarantees the dominance of fermentation by starter cultures. However, inoculated fermentations using unclarified white and red musts exhibited a consistent presence and persistence of non‐ Saccharomyces and/or Saccharomyces ‘wild’ yeasts during fermentation. The extent and composition of the initial wild microflora at the start of fermentation may affect the presence and persistence of wild Saccharomyces and non‐ Saccharomyces yeasts during guided fermentations under commercial conditions. The above findings confirm the results of previous works carried out at laboratory‐ or pilot‐scale level. Furthermore, they suggest a clear correlation between the modality of pre‐fermentative practices and the presence and persistence of ‘wild’ yeasts during fermentation. © 2002 Society of Chemical Industry