Acetaldehyde metabolism by Leuconostoc mesenteroides subsp. cremoris under stress conditions

Non-growing cells of Leuconostoc mesenteroides subsp. cremoris converted acetaldehyde to ethanol and acetate. Acetaldehyde utilisation and the formation of ethanol and acetate were influenced by pH, salt and water activity. Low pH, increased levels of salt and low water activity reduced the rates of acetaldehyde utilisation and the formation of ethanol and acetate. Almost all leuconostocs tested removed added acetaldehyde in broth co-cultures with strains of Lactococcus lactis subsp. cremoris; an exception was L. mesenteroides subsp. cremoris is 60 in co-culture with Lc. lactis subsp. cremoris 2254. L. mesenteroides subsp. cremoris 253 removed acetaldehyde produced by lactococci in milk co-cultures and the removal rate depended on the concentration of the leuconostocs and salt. (C) 1997 Elsevier Science Ltd.