Identification of metabolic pathways involved in the biosynthesis of flavor compound 3-methylbutanal from leucine catabolism by Carnobacterium maltaromaticum LMA 28

► In Carnobacterium maltaromaticum, leucine converted into 3-methylbutanal by two metabolic routes. ► Both KADC and KADH activities were detected in vitro in Carnobacterium maltaromaticum. ► Both pathways for leucine catabolism are functional in C. maltaromaticum. ► It can play a major role in cheese aroma development under certain conditions.