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Growth and end‐product formation in fermenter cultures of Brochothrix thermosphacta ATCC 11509 T and two psychrotrophic Lactobacillus spp. in different gaseous atmospheres
Author(s) -
Blickstad Elisabeth,
Molin G.
Publication year - 1984
Publication title -
journal of applied bacteriology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.889
H-Index - 156
eISSN - 1365-2672
pISSN - 0021-8847
DOI - 10.1111/j.1365-2672.1984.tb01385.x
Subject(s) - acetoin , chemistry , food science , lactic acid , lactobacillus , fermentation , acetic acid , diacetyl , biochemistry , bacteria , biology , genetics
The effects of different gaseous atmospheres were determined on the maximum specific growth rate (μ max ) and end‐product formation by Brochothrix thermosphacta ATCC 11509 T , Lactobacillus viridescens SMRICC 174 and Lactobacillus sp. SMRICC 173 (homofermentative). The highest μ max ‐values for Lact. viridescens (0.47/h) and Broc. thermosphacta (0.49/h) were obtained in air. Under anaerobic conditions μ max was reduced, an atmosphere containing CO 2 alone giving the greatest reduction. Lactobacillus sp. 173 did not grow in air or N 2 . Aerobic growth was obtained by adding peroxidase while anaerobic growth occurred in the presence of 5–20% CO 2 . Carbon dioxide alone reduced the growth rate. All test organisms produced mainly lactic acid anaerobically. Lactobacillus viridescens also produced ethanol while Broc. thermosphacta produced small amounts of ethanol and formic acid. With O 2 present, the number of end‐products increased for all organisms. Lactobacillus sp. 173 produced small amounts of acetic acid and acetoin together with lactic acid. Oxygen induced acetic acid production in Lact. viridescens and Broc. thermosphacta . Aerobically, Broc. thermosphacta also produced a large amount of acetoin and smaller amounts of 2,3‐butanediol, iso ‐valeric acid and iso ‐butyric acid. The production of lactic acid by Broc. thermosphacta was completely prevented under strictly aerobic conditions. All test organisms consumed O 2 during aerobic growth. Hydrogen peroxide was produced by Lact. viridescens and Lactobacillus sp. 173.