1. Introduction
Lactic acid bacteria (LAB) together with yeasts, characterize most of
the fermented food and they often interact in imparting the desired
characteristics to the final product. In the area of leavened goods, such
as in sourdough fermentation, LAB and yeasts contribute to acidification, flavor formation and dough leavening (De Vuyst et al., 2009;
Moroni et al., 2009).
In recent years, adverse reactions resulting from ingestion of various
food are on the rise: about 1 out of 5 adults (20%) reports food-related
hypersensitivity reactions (Lied et al., 2010). Among these, the incidence of intolerance to baker's yeast is increasing in Western population
(Mansueto et al., 2006). In a proportion of patients with Inflammatory
Bowel Disease (IBD), Saccharomyces cerevisiae wall components have
been recognized as antigens, and a cellular immune response to mannans, can be developed. Adverse reactions to baker's yeast often occur