IN-SITU AND IN REAL TIME OBSERVATION OF PARTICULATE PROCESSES IN LACTIC FERMENTATION

Abstract

Controlling bioprocesses requires understanding the behavior of bacterial populations, which necessitates real-time and in situ appropriate process monitoring techniques. Current market-available methods require various intermediate steps such as sampling, dilution, and measurement, which pose potential risks of contamination, in particular important for fermentation processes. To overcome these disadvantages, in this study, we develop a novel laser-based measurement that enables the continuously collection of bacterial population states every second under original conditions, without additional preparation steps. This innovative method allows collecting up to 25,000 to 30,000 measurement points, effectively capturing the growth, stationary, and decline phases of lactic bacteria as a case study. The robustness of the technique is evidenced by the excellent repeatability of duplicated experiments carried out under the same conditions. Additionally, via this novel method, the lactic fermentation process is observed that being significantly enhanced in the presence of turmeric and curcumin. In fact, these compounds reduce the dead rate of lactic bacteria, especially in the case of curcumin. Particularly, curcumin accelerates the growth and reproduction of L. Bulgaricus, which is in good agreement with results obtained from our developed equipment. Adding 2% (w/w) curcumin leads to an approximate 21.4% increase in the proliferation of the bacterial population. In short, this technique is highly recommended for monitoring particulate processes in biotech.