Accurate and reliable gas quantification is essential for evaluating biochemical processes in laboratory-scale reactors, yet traditional measurement methods often lack automation, require extensive manual operation, and involve high implementation costs. This study presents the design, calibration and validation of a low-cost, fully automated system for real-time gas quantification in benchtop bioreactors. The novelty of this work lies in developing a pressure-based measurement approach that ensures accuracy, repeatability and reproducibility while enabling continuous and traceable monitoring of gas production under controlled laboratory conditions. The system integrates MPX5700DP pressure sensors with an Arduino microcontroller, allowing uninterrupted pressure measurement and data logging. Calibration was performed by injecting known air volumes, yielding linear responses with R² > 0.99. System performance was validated through fermentation assays using glucose and yeast, and the resulting pressure data were converted to gas volume and fitted to a modified Gompertz model to extract kinetic parameters, including maximum gas production, production rate, and lag phase. The influence of pH and temperature on system performance was assessed through a Central Composite Design, confirming its robustness across different operational conditions. This setup offers a cost-effective, accurate, and replicable alternative to conventional gas quantification methods, improving automation, precision, and accessibility in research laboratories.
Souza et al. (Sat,) studied this question.