Malate Biosensors for the Monitoring of Malolactic Fermentation: Different Approaches

Different strategies for L‐malic acid monitoring in wine are presented in this paper. A bi‐enzymatic sensor was described based on the coupling of L‐malate dehydrogenase with NADHoxidase, while monoenzymatic systems were based either on L‐malate dehydrogenase or malate‐quinone oxidoreductase. The bienzymatic sensors showed sensitivities of 3.6 mA/M and a detection limit of 4.5 µM, while for the monoenzymatic sensors the sensitivity was 1.1 mA/M and the detection limit was 2.4 µM. The optimized biosensors were used for determination of L‐malic acid in different samples of wines.