Vanillin production from simple phenols by wine-associated lactic acid bacteria

Aims: The ability of lactic acid bacteria (LAB) to metabolize certain phenolic precursors to vanillin was investigated. Methods and Results: Gas chromatography-mass spectrometry (GC-MS) or HPLC was used to evaluate the biosynthesis of vanillin from simple phenolic precursors. LAB were not able to form vanillin from eugenol, isoeugenol or vanillic acid. However Oenococcus oeni or Lactobacillus sp. could convert ferulic acid to vanillin, but in low yield. Only Lactobacillus sp. or Pediococcus sp. strains were able to produce significant quantities of 4-vinylguaiacol from ferulic acid. Moreover, LAB reduced vanillin to the corresponding vanillyl alcohol. Conclusions: The transformation of phenolic compounds tested by LAB could not explain the concentrations of vanillin observed during LAB growth in contact with wood. Significance and Impact of the study: Important details of the role of LAB in the conversion of phenolic compounds to vanillin have been elucidated. These findings contribute to the understanding of malolactic fermentation in the production of aroma compounds.