title: Production of non-alcoholic beer using free and immobilized cells of Saccharomyces cerevisiae deficient in the tricarboxylic acid cycle.
abstract: Production of non-alcoholic beer using Saccharomyces cerevisiae has been studied. Non-recombinant mutant strains with a defect in the synthesis of tricarboxylic-acid-cycle enzymes were used and applied in both free and pectate-immobilized form, using both batch and packed-bed continuous systems. After fermentation, basic parameters of the beer produced by five mutant strains were compared with a standard strain of brewing yeast. Results showed that the beer prepared by mutant yeast cells was characterized by lower levels of total alcohols, with ethanol concentrations between 0.07 and 0.31% (w/w). The organic acids produced, especially lactic acid, in concentrations up to 1.38 g x l(-1) had a strong protective effect on the microbial stability of the final product and thus the usual addition of lactic acid could be omitted. Application of the yeast mutants appears to be a good alternative to the classical methods for the production of non-alcoholic beer.
authors.affiliation: Department of Biochemical Technology, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, SK-81237 Bratislava, Slovak Republic. navratil@chelin.chtf.stuba.sk
authors.forename: Marián
authors.initials: M
authors.lastname: Navrátil
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Dömény
authors.forename: Ernest
authors.initials: E
authors.lastname: Sturdík
authors.forename: Daniela
authors.initials: D
authors.lastname: Smogrovicová
authors.forename: Peter
authors.initials: P
authors.lastname: Gemeiner
mesh_terms: D001515:Beer; D018914:Cells, Immobilized / Q000378:metabolism; D002952:Citric Acid Cycle; D000431:Ethanol; D005285:Fermentation; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000378:metabolism*; D013535:Suspensions
chemical_list: D013535:Suspensions; D000431:Ethanol