title: L-(-)-malic acid production by Saccharomyces spp. during the alcoholic fermentation of wine (1).
abstract: In an attempt to increase the acidity of wine by biological means, malate-producing yeasts were selected from a collection of 282 strains isolated in different parts of Spain. Only 4% of these strains (all of which belonged to Saccharomyces cerevisiae) produced l-(-)-malic acid in the range of 0.5-1 g/L. This was formed between days 2 and 6 of alcoholic fermentation, reaching a maximum on days 3 and 4; the concentration remained stable from day 7. Malic acid production was favored by temperatures in the 18-25 degrees C range and by musts with a high pH and low concentrations of sugar, initial malic acid, and yeast-assimilable nitrogen. Oxaloacetic acid, a precursor of malic acid, had no influence on malate production. The precursors pyruvic and fumaric acid did, however, have a significant effect on the production of this acid in some strains. No direct relation between pyruvate and malate metabolism was observed.
authors.affiliation: Departamento de Tecnología de Alimentos and Departamento de Estadística y Métodos de Gestión en Agricultura, Escuela Técnica Superior de Ingenieros Agrónomos, Universidad Politécnica de Madrid, 28040 Madrid, Spain. ynadine@hotmail.com
authors.forename: N
authors.initials: N
authors.lastname: Yéramian
authors.forename: C
authors.initials: C
authors.lastname: Chaya
authors.forename: J A
authors.initials: JA
authors.lastname: Suárez Lepe
mesh_terms: D055598:Chemical Phenomena; D002627:Chemistry, Physical; D005285:Fermentation; D006863:Hydrogen-Ion Concentration; D008293:Malates / Q000378:metabolism*; D019289:Pyruvic Acid / Q000378:metabolism; D012440:Saccharomyces / Q000378:metabolism*; D013045:Species Specificity; D013696:Temperature; D014920:Wine / Q000032:analysis* / Q000382:microbiology*
chemical_list: D008293:Malates; C030298:malic acid; D019289:Pyruvic Acid