Effect of oxidoreduction potential on aroma biosynthesis by lactic acid bacteria in nonfat yogurt.
The aim of this study was to investigate the effect of oxidoreduction potential (Eh) on the biosynthesis of aroma compounds by lactic acid bacteria in non-fat yogurt. The study was done with yogurts fermented by Lactobacillus bulgaricus and Streptococcus thermophilus. The Eh was modified by the application of different gaseous conditions (air, nitrogen, and nitrogen/hydrogen). Acetaldehyde, dimethyl sulfide, diacetyl, and pentane-2,3-dione, as the major endogenous odorant compounds of yogurt, were chosen as tracers for the biosynthesis of aroma compounds by lactic acid bacteria. Oxidative conditions favored the production of acetaldehyde, dimethyl sulfide, and diketones (diacetyl and pentane-2,3-dione). The Eh of the medium influences aroma production in yogurt by modifying the metabolic pathways of Lb. bulgaricus and Strep. thermophilus. The use of Eh as a control parameter during yogurt production could permit the control of aroma formation.
Laboratoire de Génie des Procédés Microbiologiques et Alimentaires, EA 1684, AgroSup Dijon-Université de Bourgogne, INRA, 17 rue Sully, 21065 Dijon, France.
F
F
Martin
R
R
Cachon
K
K
Pernin
J
J
De Coninck
P
P
Gervais
E
E
Guichard
N
N
Cayot
D000818:Animals; D004041:Dietary Fats / Q000032:analysis; D005285:Fermentation; D005516:Food Microbiology; D019344:Lactic Acid; D007778:Lactobacillus / Q000145:classification / Q000378:metabolism*; D010084:Oxidation-Reduction; D012903:Smell; D048249:Streptococcus thermophilus / Q000378:metabolism*; D015014:Yogurt / Q000032:analysis* / Q000382:microbiology*
D004041:Dietary Fats; D019344:Lactic Acid