In wine industry, the malolactic fermentation, employed to lower the overall tartness of wine, is usually monitored by following the diminishing level of L-malic acid and the increasing level of L-lactic acid. Consequently, the monitoring of L-lactic acid levels in the course of the fermentation plays an important role in wine quality testing [1-2]. L-lactic acid is typically determined using chromatography based techniques. However, although these methods are precise, require bulky instrumentation, trained personnel and are costly. Therefore, electrochemical biosensors appear as promising alternative for the development of simple, fast, low-cost and portable platforms for in situ L-lactic acid analysis.

In this work, an enzymatic electrochemical sensor for the determination of L- lactic acid in wine samples has been developed. These single-use, small sized, sensors allowed the specific determination of L-lactic acid between 0.02 mM and 0.3 mM. Different wine samples were assayed with the proposed sensors and the obtained results indicate that the developed methodology has an accurate performance.

In summary, these enzymatic electrochemical sensors revealed to be robust, highly stable, user-friendly and time-saving, demonstrating the possibility of being used for the decentralized monitoring of L-Lactic acid in wine samples as an analytical trustful tool.

References

[1] Analytical and Bioanalytical Chemistry (2014) 406:123–137.

[2] Biochemistry and Biophysics Reports (2016) 5:35–54.