The current study focused on tracking the biogas pathways in the internal loop airlift bioreactor under conditions of metabolic consumption. The focus of the investigation was simultaneously set on the wastewater produced by the dairy industry. Two stages were used to conduct this investigation. Using the Taguchi model, an optimization study of the bioreactor's operating conditions was conducted as the first step. The experimental findings demonstrated a distinct impact of the biogas flow rate on the overall mass transfer coefficient compared with the other operating parameters (liquid type and volume). By analyzing the S/N ratio and ANOVA analysis, the best level was determined for each parameter studied. The optimal factors were also identified (flow rate = 50, volume = 5.5, type of sol.= whey). These optimization values were then applied in real bacteria bio-consumption. The biogas consumed by the organism was also reduced from 50 to 25 liters/hour, thus saving 50 % of the energy consumed.